Migrate (i.e. move) `tools/bazel.rc` to `.bazelrc`

Since [1], Bazel changed the list of resource file locations. Adapt to
that list so move `%workspace%/tools/bazelrc` to `%workspace%/.bazelrc`.

[1] https://github.com/bazelbuild/bazel/commit/ec83598

Change-Id: I8eefb9b4c1703811eb6979170e2d22ceb01e683e
1 file changed