//tests:m4_test fails to build on Windows due to incorrect header inclusion check

[jmillikin]

See bazelbuild/bazel#5640 for background.

(00:26:15) ERROR: D:/b/llkfrd43/external/bazel_tools/tools/cpp/runfiles/BUILD:3:1: Couldn't build file external/bazel_tools/tools/cpp/runfiles/_objs/runfiles/runfiles.obj: undeclared inclusion(s) in rule '@bazel_tools//tools/cpp/runfiles:runfiles':
--
  | this rule is missing dependency declarations for the following files included by 'external/bazel_tools/tools/cpp/runfiles/runfiles.cc':
  | 'D:/b/j4my5y73/execroot/bazel_skylib/external/bazel_tools/tools/cpp/runfiles/runfiles.h'

[jmillikin]

See also 047c793, which may be a viable workaround that could be upstreamed to Bazel.

[jmillikin]

I don't remember the context behind this issue, but the tests are currently passing on Windows in CI. It was possibly fixed by a newer Bazel version.