A recent-ish change to allow unicode character classes to be used
with "grep -P" triggered a JIT bug in older pcre2 libraries.
The problematic change in Git built with these older libraries has
been disabled to work around the bug.
* mk/workaround-pcre-jit-ucp-bug:
grep: work around UTF-8 related JIT bug in PCRE2 <= 10.34