Stop relying on rbe-windows-credentials.json

tools/internal_ci/windows/bazel_rbe.bat

@@ -24,7 +24,7 @@ powershell -Command "[guid]::NewGuid().ToString()" >%KOKORO_ARTIFACTS_DIR%/bazel
 set /p BAZEL_INVOCATION_ID=<%KOKORO_ARTIFACTS_DIR%/bazel_invocation_ids
 
 @rem TODO(jtattermusch): windows RBE should be able to use the same credentials as Linux RBE.
-bazel --bazelrc=tools/remote_build/windows.bazelrc test --invocation_id="%BAZEL_INVOCATION_ID%" %BAZEL_FLAGS% --workspace_status_command=tools/remote_build/workspace_status_kokoro.bat --google_credentials=%KOKORO_GFILE_DIR%/rbe-windows-credentials.json //test/...
+bazel --bazelrc=tools/remote_build/windows.bazelrc test --invocation_id="%BAZEL_INVOCATION_ID%" %BAZEL_FLAGS% --workspace_status_command=tools/remote_build/workspace_status_kokoro.bat //test/...
 set BAZEL_EXITCODE=%errorlevel%
 
 if not "%UPLOAD_TEST_RESULTS%"=="" (

tools/internal_ci/windows/grpc_bazel_rbe_dbg.cfg

@@ -21,7 +21,6 @@ timeout_mins: 90
 
 gfile_resources: "/bigstore/grpc-testing-secrets/gcp_credentials/GrpcTesting-d0eeee2db331.json"
 gfile_resources: "/bigstore/grpc-testing-secrets/gcp_credentials/resultstore_api_key"
-gfile_resources: "/bigstore/grpc-testing-secrets/gcp_credentials/rbe-windows-credentials.json"
 
 bazel_setting {
   # In order for Kokoro to recognize this as a bazel build and publish the bazel resultstore link,

tools/internal_ci/windows/grpc_bazel_rbe_opt.cfg

@@ -21,7 +21,6 @@ timeout_mins: 90
 
 gfile_resources: "/bigstore/grpc-testing-secrets/gcp_credentials/GrpcTesting-d0eeee2db331.json"
 gfile_resources: "/bigstore/grpc-testing-secrets/gcp_credentials/resultstore_api_key"
-gfile_resources: "/bigstore/grpc-testing-secrets/gcp_credentials/rbe-windows-credentials.json"
 
 bazel_setting {
   # In order for Kokoro to recognize this as a bazel build and publish the bazel resultstore link,

tools/internal_ci/windows/pull_request/grpc_bazel_rbe_dbg.cfg

@@ -21,7 +21,6 @@ timeout_mins: 90
 
 gfile_resources: "/bigstore/grpc-testing-secrets/gcp_credentials/GrpcTesting-d0eeee2db331.json"
 gfile_resources: "/bigstore/grpc-testing-secrets/gcp_credentials/resultstore_api_key"
-gfile_resources: "/bigstore/grpc-testing-secrets/gcp_credentials/rbe-windows-credentials.json"
 
 bazel_setting {
   # In order for Kokoro to recognize this as a bazel build and publish the bazel resultstore link,

tools/internal_ci/windows/pull_request/grpc_bazel_rbe_opt.cfg

@@ -21,7 +21,6 @@ timeout_mins: 90
 
 gfile_resources: "/bigstore/grpc-testing-secrets/gcp_credentials/GrpcTesting-d0eeee2db331.json"
 gfile_resources: "/bigstore/grpc-testing-secrets/gcp_credentials/resultstore_api_key"
-gfile_resources: "/bigstore/grpc-testing-secrets/gcp_credentials/rbe-windows-credentials.json"
 
 bazel_setting {
   # In order for Kokoro to recognize this as a bazel build and publish the bazel resultstore link,