Bump haskell-actions/setup from 2.7.3 to 2.7.6

Bumps [haskell-actions/setup](https://github.com/haskell-actions/setup) from 2.7.3 to 2.7.6.
- [Release notes](https://github.com/haskell-actions/setup/releases)
- [Commits](haskell-actions/setup@v2.7.3...v2.7.6)

---
updated-dependencies:
- dependency-name: haskell-actions/setup
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

Author: dependabot[bot]

Diff for: .github/workflows/bench.yml

@@ -127,7 +127,7 @@ jobs:
         example: ['cabal', 'lsp-types']
 
     steps:
-    - uses: haskell-actions/[email protected].3
+    - uses: haskell-actions/[email protected].6
       with:
         ghc-version  : ${{ matrix.ghc   }}
         cabal-version: ${{ matrix.cabal }}