Bump third_party/editline/repo from 4255848 to 50bde4b

Bumps [third_party/editline/repo](https://github.com/troglobit/editline) from `4255848` to `50bde4b`.
- [Release notes](https://github.com/troglobit/editline/releases)
- [Commits](troglobit/editline@4255848...50bde4b)

---
updated-dependencies:
- dependency-name: third_party/editline/repo
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <[email protected]>