Emit LLVM coverage for source file paths with a `tmp` segment

[fmeum]

The LLVM LCOV coverage collection logic attempted to filter out source files under /tmp/, but instead filtered out all source files with paths containing the substring /tmp/. Under macOS, where Bazel's output base lies under /private/var/tmp, this matched every output base absolute path.

[fmeum]

@c-mita Could you review this PR?

[fmeum]

@c-mita Friendly ping

[fmeum]

@c-mita @sgowroji Friendly ping, does this need to be transitioned to "awaiting-merge"?

[sgowroji]

Hello @c-mita, Can you please confirm to import the above PR changes.

[c-mita]

Oops. Yes, this should be imported.

[fmeum]

@bazel-io flag

[ShreeM01]

@bazel-io fork 6.1.0