renode: use robotframework at 6.0.2

Renode expects a specific version or it keeps warning about. Fixes:

,----
| Required `robotframework` version is `6.0.2`, while the one available in
| your system is `7.0.0`. Tests may still work, but this version of Robot
| is not officially supported. Please install the required version using
| `pip install robotframework==6.0.2` before running the tests
`----

Signed-off-by: Otavio Salvador <otavio@ossystems.com.br>

pkgs/by-name/re/renode/package.nix

@@ -1,5 +1,6 @@
 { stdenv
 , lib
+, fetchFromGitHub
 , fetchurl
 , autoPatchelfHook
 , makeWrapper
@@ -17,7 +18,15 @@ let
     psutil
     pyyaml
     requests
-    robotframework
+
+    (robotframework.overrideDerivation (oldAttrs: {
+      src = fetchFromGitHub {
+        owner = "robotframework";
+        repo = "robotframework";
+        rev = "v6.0.2";
+        hash = "sha256-c7pPcDgqyqWQtiMbLQbQd0nAgx4TIFUFHrlBVDNdr8M=";
+      };
+    }))
   ];
 in
 stdenv.mkDerivation (finalAttrs: {