archivers/php-brotli: Update to version 0.13.1

View changes to this version here:
https://github.com/kjdev/php-ext-brotli/commits/c17297688a6c7d23be33f170405f099aa7cd0d38

Submitted by: Daniel Shafer <daniel@shafer.cc> (maintainer)
Differential Revision: https://reviews.freebsd.org/D29346