Simplify globbing for casks and formula in taps

[apainintheneck]

• Have you followed the guidelines in our Contributing document?
• Have you checked to ensure there aren't other open Pull Requests for the same change?
• Have you added an explanation of what your changes do and why you'd like us to include them?
• Have you written new tests for your changes? Here's an example.
• Have you successfully run brew style with your changes locally?
• Have you successfully run brew typecheck with your changes locally?
• Have you successfully run brew tests with your changes locally?

---

TLDR: @Bo98 was right in #18165 (comment).

This is yet another approach to f3a5a3c which got merged in over the weekend. It is much simpler than what we've got now with almost exactly the same performance characteristics. A better combination of maintainability and performance.

$ hyperfine --parameter-list branch master,speed-up-loading-cask-and-formula-file-names_v4 --warmup 5 --setup 'git switch {branch}' 'brew cat gimp'
Benchmark 1: brew cat gimp (branch = master)
  Time (mean ± σ):      1.459 s ±  0.012 s    [User: 0.892 s, System: 0.536 s]
  Range (min … max):    1.448 s …  1.483 s    10 runs

Benchmark 2: brew cat gimp (branch = speed-up-loading-cask-and-formula-file-names_v4)
  Time (mean ± σ):      1.456 s ±  0.009 s    [User: 0.889 s, System: 0.536 s]
  Range (min … max):    1.445 s …  1.468 s    10 runs

Summary
  brew cat gimp (branch = speed-up-loading-cask-and-formula-file-names_v4) ran
    1.00 ± 0.01 times faster than brew cat gimp (branch = master)

[MikeMcQuaid]

Much nicer, thanks!