Bump haskell-actions/setup in /.github/actions/setup-build (#4476)

Bumps [haskell-actions/setup](https://github.com/haskell-actions/setup) from 2.7.7 to 2.7.8.
- [Release notes](https://github.com/haskell-actions/setup/releases)
- [Commits](haskell-actions/setup@v2.7.7...v2.7.8)

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

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

.github/actions/setup-build/action.yml

@@ -31,7 +31,7 @@ runs:
         sudo chown -R $USER /usr/local/.ghcup
       shell: bash
 
-    - uses: haskell-actions/[email protected].7
+    - uses: haskell-actions/[email protected].8
       id: HaskEnvSetup
       with:
         ghc-version  : ${{ inputs.ghc   }}