[Slackbuilds-users] gumbo-parser update to 0.13.2

[B. Watson]

I'm updating gumbo-parser again, to 0.13.2. This should be a seamless
upgrade for all builds that depend on gumbo-parser: the src/ directory
hasn't changed since 0.13.1. Only the build stuff (autoconf and meson;
we're using meson), documentation, and self-test suite (fuzz/) have
changed.

I test-built everything that depends on gumbo-parser, and it's all
fine. I'm basically sending this out to save everyone from worrying
that the update might break their builds (it won't).