wabt: 1.0.19 -> 1.0.20

For some unknown reason, the version built here reports
itself as 1.0.13 (e.g. in `wasm-objdump --version`).

That is unfortunate, but seems to match what happened in
the release binaries published on github:
- https://github.com/WebAssembly/wabt/releases/tag/1.0.20
  these report 1.0.13 for me, too, on macos.
- https://github.com/WebAssembly/wabt/issues/1463

Signed-off-by: Stephan Renatus <stephan.renatus@gmail.com>

pkgs/development/tools/wabt/default.nix

@@ -2,22 +2,16 @@
 
 stdenv.mkDerivation rec {
   pname = "wabt";
-  version = "1.0.19";
+  version = "1.0.20";
 
   src = fetchFromGitHub {
     owner = "WebAssembly";
     repo = "wabt";
     rev = version;
-    sha256 = "0g1iy1icnjfkc0dadkrif4nlixpvq626023rgj02m9al64gf9hvx";
+    sha256 = "1wwyljppxz03slvgx809g87mdrglpimz4xaici71a9mqwjpgj0l8";
     fetchSubmodules = true;
   };
 
-  # https://github.com/WebAssembly/wabt/pull/1408
-  patches = [ (fetchpatch {
-    url = "https://github.com/WebAssembly/wabt/pull/1408/commits/28505f4db6e4561cf6840af5c304a9aa900c4987.patch";
-    sha256 = "1nh1ddsak6w51np17xf2r7i0czxrjslz1i4impmmp88h5bp2yjba";
-  }) ];
-
   nativeBuildInputs = [ cmake ];
   cmakeFlags = [ "-DBUILD_TESTS=OFF" "-DCMAKE_PROJECT_VERSION=${version}" ];
   buildInputs = [ python3 ];