Fix build-git target on musl-based systems

By default, Git will assume that the regex implementation of libc support the REG_STARTEND feature. As this feature started out as a non-standard glibc extension, it's not available to all systems. Most notably, musl libc doesn't implement it as it tries to be as strictly POSIX compliant as it makes sense.

Fix the issue by amending NO_REGEX=YesPlease to Git's build options. This will cause it to use its own embedded regex implementation which obviously supports this feature.