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/lint.yml

@@ -19,7 +19,7 @@ jobs:
           # Use the lowest version of Python supported
           python-version: "3.7"
 
-      - uses: actions/cache@v3
+      - uses: actions/cache@v4
         with:
           path: ~/.cache/pip
           key: setup-python-${{ runner.os }}-mypy-pip-${{ hashFiles('**/setup.cfg') }}

.github/workflows/main.yml

@@ -30,7 +30,7 @@ jobs:
         with:
           python-version: ${{ matrix.python-version }}
 
-      - uses: actions/cache@v3
+      - uses: actions/cache@v4
         with:
           path: ~/.cache/pip
           key: setup-python-${{ runner.os }}-python-${{ matrix.python-version }}-pip-${{ hashFiles('**/setup.cfg') }}