legacylibrarian: failing to parse googleapis commit message

The commit: https://github.com/googleapis/googleapis/commit/df13ea51961ff225a825beab9ca112188de367a3

For some reason there is no space between `feat:` and the description. This is breaking our parser. Let's allow 0 or 1 space.
Related to internal bug: b/484072737