[Bzlmod] Add --nobuild to bzlmod build test for cheaper validation. (#41431)

https://github.com/grpc/grpc/pull/41309 caused timeout because a full
build is too expensive.

This PR changes the new bazel command to use the --nobuild option. This
triggers bazel's "static" dependency analysis without compiling C++
code. This test does NOT detect issues caused by module
incompatibilities (e.g. some package doesn't build with new version of
absl).

---------

Co-authored-by: Mark D. Roth <roth@google.com>

tools/bazelify_tests/test/bazel_build_with_bzlmod_linux.sh

@@ -43,9 +43,14 @@ tools/bazel \
     //test/core/util:all \
     //test/cpp/common:all
 
+# Use --nobuild flag to trigger bazel dependency analysis but skip C++
+# compilation.
+# TODO(weizheyuan): Re-enable the full build (by removing --nobuild)
+# once it no longer causes CI timeouts.
 tools/bazel \
     --bazelrc=tools/remote_build/linux_bzlmod.bazelrc \
     build \
+    --nobuild \
     --ignore_dev_dependency=false \
     -- \
     //test/... \