treewide: remove <packing> from Adwaita widgets

Part-of: <https://gitlab.gnome.org/GNOME/calls/-/merge_requests/714>

plugins/provider/sip/sip-account-widget.ui

@@ -10,7 +10,7 @@
           <object class="AdwHeaderBar" id="header_add">
             <property name="title" translatable="yes">Add Account</property>
             <property name="show-close-button">True</property>
-            <child>
+            <child type="end">
               <object class="GtkButton" id="login_btn">
                 <property name="use-underline">True</property>
                 <property name="label" translatable="yes">_Log In</property>
@@ -19,15 +19,9 @@
                   <class name="suggested-action"/>
                 </style>
               </object>
-              <packing>
-                <property name="pack_type">end</property>
-              </packing>
             </child>
-            <child>
+            <child type="end">
               <object class="GtkSpinner" id="spinner_add"/>
-              <packing>
-                <property name="pack_type">end</property>
-              </packing>
             </child>
           </object>
         </child>
@@ -36,7 +30,7 @@
             <property name="visible">True</property>
             <property name="show-close-button">True</property>
             <property name="title" translatable="yes">Manage Account</property>
-            <child>
+            <child type="end">
               <object class="GtkButton" id="apply_btn">
                 <property name="use-underline">True</property>
                 <property name="label" translatable="yes">_Apply</property>
@@ -45,11 +39,8 @@
                   <class name="suggested-action"/>
                 </style>
               </object>
-              <packing>
-                <property name="pack_type">end</property>
-              </packing>
             </child>
-            <child>
+            <child type="end">
               <object class="GtkButton" id="delete_btn">
                 <property name="use-underline">True</property>
                 <property name="label" translatable="yes">_Delete</property>
@@ -58,15 +49,9 @@
                   <class name="destructive-action"/>
                 </style>
               </object>
-              <packing>
-                <property name="pack_type">end</property>
-              </packing>
             </child>
-            <child>
+            <child type="end">
               <object class="GtkSpinner" id="spinner_edit"/>
-              <packing>
-                <property name="pack_type">end</property>
-              </packing>
             </child>
           </object>
         </child>

src/ui/account-overview.ui

@@ -15,11 +15,8 @@
             <property name="title" translatable="yes">VoIP Accounts</property>
             <property name="show-close-button">True</property>
             <property name="visible">True</property>
-            <child>
+            <child type="end">
               <object class="GtkSpinner" id="spinner"/>
-              <packing>
-                <property name="pack_type">end</property>
-              </packing>
             </child>
           </object>
         </child>

src/ui/main-window.ui

@@ -23,7 +23,7 @@
                 <property name="title" bind-source="CallsMainWindow" bind-property="title" bind-flags="sync-create"/>
               </object>
             </child>
-            <child>
+            <child type="end">
               <object class="GtkMenuButton">
                 <property name="popover">menu_popover</property>
                 <child>
@@ -32,9 +32,6 @@
                   </object>
                 </child>
               </object>
-              <packing>
-                <property name="pack_type">end</property>
-              </packing>
             </child>
           </object>
         </child>
@@ -95,7 +92,7 @@
         <property name="visible">True</property>
         <property name="show-close-button">False</property>
         <property name="title" translatable="yes">USSD</property>
-        <child>
+        <child type="start">
           <object class="GtkButton" id="ussd_cancel_button">
             <property name="has-default">True</property>
             <property name="can-default">True</property>
@@ -103,11 +100,8 @@
             <property name="label" translatable="yes">_Cancel</property>
             <signal name="clicked" handler="window_ussd_cancel_clicked_cb" swapped="yes"/>
           </object>
-          <packing>
-            <property name="pack_type">start</property>
-          </packing>
         </child>
-        <child>
+        <child type="start">
           <object class="GtkButton" id="ussd_close_button">
             <property name="visible" bind-source="ussd_cancel_button" bind-property="visible" bind-flags="sync-create|invert-boolean|bidirectional"/>
             <property name="has-default">True</property>
@@ -116,11 +110,8 @@
             <property name="label" translatable="yes">_Close</property>
             <signal name="clicked" handler="gtk_window_close" object="ussd_dialog" swapped="yes"/>
           </object>
-          <packing>
-            <property name="pack_type">start</property>
-          </packing>
         </child>
-        <child>
+        <child type="end">
           <object class="GtkButton" id="ussd_reply_button">
             <property name="label" translatable="yes">_Send</property>
             <property name="sensitive">False</property>
@@ -130,9 +121,6 @@
               <class name="suggested-action"/>
             </style>
           </object>
-          <packing>
-            <property name="pack-type">end</property>
-          </packing>
         </child>
       </object>
     </child>