Use-case: While not a vogue technology, VB is still a common file type taught in many university settings and used in many commercial settings. Working with VB files out-of-the-box would provide a lot of value to `ripgrep` users.
Example: I'm working on converting a legacy app to a modern infrastructure. The legacy app mixes CS and VB files liberally, so I always need to check both. For portability, it would be nice to just be able to ask for `-tcs -tvb` without registering with `--type-add` first.
Tests: I didn't notice any coverage aimed at this part of the code, but if I'm mistaken I'll amend the PR.