Bump stripe from 14.0.0 to 15.0.0 (#2105)

Bumps [stripe](https://github.com/stripe/stripe-ruby) from 14.0.0 to 15.0.0.
- [Release notes](https://github.com/stripe/stripe-ruby/releases)
- [Changelog](https://github.com/stripe/stripe-ruby/blob/master/CHANGELOG.md)
- [Commits](https://github.com/stripe/stripe-ruby/compare/v14.0.0...v15.0.0)

---
updated-dependencies:
- dependency-name: stripe
  dependency-version: 15.0.0
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Co-authored-by: Zach Gollwitzer <zach@maybe.co>

Gemfile.lock

@@ -477,7 +477,7 @@ GEM
     stimulus-rails (1.3.4)
       railties (>= 6.0.0)
     stringio (3.1.5)
-    stripe (14.0.0)
+    stripe (15.0.0)
     tailwindcss-rails (4.2.1)
       railties (>= 7.0.0)
       tailwindcss-ruby (~> 4.0)