bazel_4: use correct bazel version for tests

`bazel_self` is the current package. If we do not specify it explicitly when defining tests then Bazel 3 is used by default.

pkgs/development/tools/build-managers/bazel/bazel_4/default.nix

@@ -323,13 +323,13 @@ stdenv.mkDerivation rec {
 
     in (if !stdenv.hostPlatform.isDarwin then {
       # `extracted` doesn’t work on darwin
-      shebang = callPackage ../shebang-test.nix { inherit runLocal extracted bazelTest distDir; };
+      shebang = callPackage ../shebang-test.nix { inherit runLocal extracted bazelTest distDir; bazel = bazel_self; };
     } else {}) // {
-      bashTools = callPackage ../bash-tools-test.nix { inherit runLocal bazelTest distDir; };
-      cpp = callPackage ../cpp-test.nix { inherit runLocal bazelTest bazel-examples distDir; };
-      java = callPackage ../java-test.nix { inherit runLocal bazelTest bazel-examples distDir; };
-      protobuf = callPackage ../protobuf-test.nix { inherit runLocal bazelTest distDir; };
-      pythonBinPath = callPackage ../python-bin-path-test.nix { inherit runLocal bazelTest distDir; };
+      bashTools = callPackage ../bash-tools-test.nix { inherit runLocal bazelTest distDir; bazel = bazel_self; };
+      cpp = callPackage ../cpp-test.nix { inherit runLocal bazelTest bazel-examples distDir; bazel = bazel_self; };
+      java = callPackage ../java-test.nix { inherit runLocal bazelTest bazel-examples distDir; bazel = bazel_self; };
+      protobuf = callPackage ../protobuf-test.nix { inherit runLocal bazelTest distDir; bazel = bazel_self; };
+      pythonBinPath = callPackage ../python-bin-path-test.nix { inherit runLocal bazelTest distDir; bazel = bazel_self; };
 
       bashToolsWithNixHacks = callPackage ../bash-tools-test.nix { inherit runLocal bazelTest distDir; bazel = bazelWithNixHacks; };