Bump actions/cache from 3 to 4

Bumps [actions/cache](https://github.com/actions/cache) from 3 to 4.
- [Release notes](https://github.com/actions/cache/releases)
- [Changelog](https://github.com/actions/cache/blob/main/RELEASES.md)
- [Commits](actions/cache@v3...v4)

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

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

Author: dependabot[bot]

.github/workflows/poseidon.yml

@@ -130,7 +130,7 @@ jobs:
       # Cache Poseidon binary
       - name: Cache Poseidon binary
         id: cache-poseidon
-        uses: actions/cache@v3
+        uses: actions/cache@v4
         with:
           path: ~/.cargo/bin/poseidon
           key: poseidon-${{ runner.os }}-${{ steps.poseidon-sha.outputs.sha }}

.github/workflows/steel.yml

@@ -146,7 +146,7 @@ jobs:
         run: |
           echo "SCCACHE_GHA_ENABLED=true" >> $GITHUB_ENV
           echo "RUSTC_WRAPPER=sccache" >> $GITHUB_ENV
-      - uses: actions/cache@v3
+      - uses: actions/cache@v4
         with:
           path: ~/.cargo/bin/steel
           key: ${{ runner.os }}-steel-cli