GA(deps): Bump fourmolu/fourmolu-action from 6 to 7

Bumps [fourmolu/fourmolu-action](https://github.com/fourmolu/fourmolu-action) from 6 to 7.
- [Release notes](https://github.com/fourmolu/fourmolu-action/releases)
- [Changelog](https://github.com/fourmolu/fourmolu-action/blob/master/CHANGELOG.md)
- [Commits](haskell-actions/run-fourmolu@v6...v7)

---
updated-dependencies:
- dependency-name: fourmolu/fourmolu-action
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

Author: dependabot[bot]

.github/workflows/ci.yml

@@ -117,7 +117,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v2
-      - uses: fourmolu/fourmolu-action@v6
+      - uses: fourmolu/fourmolu-action@v7
 
   hlint:
     runs-on: ubuntu-latest