[clang-tidy][NFC] Move CachedGlobList to GlobList.h

Currently it's hidden inside ClangTidyDiagnosticConsumer,
so it's hard to know it exists.

Given that there are multiple uses of globs in clang-tidy,
it makes sense to have these classes publicly available
for other use cases that might benefit from it.

Also, add unit test by converting the existing tests
for GlobList into typed tests.

Reviewed By: salman-javed-nz

Differential Revision: https://reviews.llvm.org/D113422