[CI] Try to remove frama_c_clang from internal

nix/default.nix

@@ -237,8 +237,8 @@ rec {
            chmod -R u+w -- "$sourceRoot/src/plugins/counter-examples"
            cp -r --preserve=mode "$genassigns_src" "$sourceRoot/src/plugins/genassigns"
            chmod -R u+w -- "$sourceRoot/src/plugins/genassigns"
-           cp -r --preserve=mode "$frama_clang_src" "$sourceRoot/src/plugins/frama-clang"
-           chmod -R u+w -- "$sourceRoot/src/plugins/frama-clang"
+           # cp -r --preserve=mode "$frama_clang_src" "$sourceRoot/src/plugins/frama-clang"
+           # chmod -R u+w -- "$sourceRoot/src/plugins/frama-clang"
            cp -r --preserve=mode "$pathcrawler_src" "$sourceRoot/src/plugins/pathcrawler"
            chmod -R u+w -- "$sourceRoot/src/plugins/pathcrawler"
            cp -r --preserve=mode "$mthread_src" "$sourceRoot/src/plugins/mthread"