Bump utils/wesnoth-map-diff from 2f9c504 to 6849d99

Bumps [utils/wesnoth-map-diff](https://github.com/cooljeanius/wesnoth-map-diff) from `2f9c504` to `6849d99`.
- [Release notes](https://github.com/cooljeanius/wesnoth-map-diff/releases)
- [Commits](cooljeanius/wesnoth-map-diff@2f9c504...6849d99)

---
updated-dependencies:
- dependency-name: utils/wesnoth-map-diff
  dependency-type: direct:production
...

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