Use case-sensitive regular expressions in --no-compress-regex

On some windows versions (plus wine) std::regex has issues with the
icase flag (making regex case insensitive). Put the responsibility of
the case sensitivity on the caller.

Fixes: 127793905
Test: wine aapt2_tests.exe -> Util_test
Change-Id: I6775514d3ef43c2c47465bf39ceaf2c195909724