Follow-up from "Blob refactor: Add ability to lock/unlock a blob"
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The following discussion from !67408 should be addressed:
- [ ] @rob.hunt started a [discussion](https://gitlab.com/gitlab-org/gitlab/-/merge_requests/67408#note_643885870): (+1 comment)
> **suggestion (non-blocking):** WDYT about using `GlModal` like the replace and delete buttons? If you agree, happy for this to be a follow-up
### Context
Before we refactored the Lock button we were using `window.confirm` to confirm whether or not a user wants to lock/unlock a file. When we refactored the code we kept `window.confirm` and decided to implement a `GlModal` dialog in a follow-up.
This is a proposal to rather use `GlModal` instead of `window.confirm`.
issue