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] <support@github.com>

.github/workflows/py-dead-code.yml

@@ -20,7 +20,7 @@ jobs:
           python-version: '3.9'
 
       - name: "Cache pip"
-        uses: actions/cache@v3
+        uses: actions/cache@v4
         with:
           # This path is specific to Ubuntu
           path: ~/.cache/pip

.github/workflows/py-test.yml

@@ -28,7 +28,7 @@ jobs:
           python-version: '3.11'
 
       - name: "Cache pip"
-        uses: actions/cache@v3
+        uses: actions/cache@v4
         with:
           # This path is specific to Ubuntu
           path: ~/.cache/pip
@@ -82,7 +82,7 @@ jobs:
           python-version: ${{ matrix.python-version }}
 
       - name: "Cache pip"
-        uses: actions/cache@v3
+        uses: actions/cache@v4
         with:
           # This path is specific to Ubuntu
           path: ~/.cache/pip

.github/workflows/release.yml

@@ -60,7 +60,7 @@ jobs:
 
       - name: "Cache pip"
         if: env.release_version != '' && success()
-        uses: actions/cache@v3
+        uses: actions/cache@v4
         with:
           # This path is specific to Ubuntu
           path: ~/.cache/pip