Bump actions/cache from 4 to 5

Bumps [actions/cache](https://github.com/actions/cache) from 4 to 5.
- [Release notes](https://github.com/actions/cache/releases)
- [Changelog](https://github.com/actions/cache/blob/main/RELEASES.md)
- [Commits](actions/cache@v4...v5)

---
updated-dependencies:
- dependency-name: actions/cache
  dependency-version: '5'
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

.github/workflows/ci.yml

@@ -58,7 +58,7 @@ jobs:
         with:
           extra_nix_config: |
             accept-flake-config = true
-      - uses: actions/cache@v4
+      - uses: actions/cache@v5
         with:
           path: |
             ~/.ghc-wasm/.cabal/store
@@ -98,7 +98,7 @@ jobs:
         with:
           enable-stack: true
           stack-no-global: true
-      - uses: actions/cache@v4
+      - uses: actions/cache@v5
         with:
           path: ~/.stack
           key: stack-${{ hashFiles('stack.yaml', 'ormolu.cabal') }}