fixing sunsetting gha actions/cache@v2

 * Replace with `actions/cache@v4`. No other changes needed?

Author: felliott

.github/workflows/test-build.yml

@@ -21,7 +21,7 @@ jobs:
           python-version: ${{ matrix.python-version }}
       - name: Cache Build Requirements
         id: pip-cache-step
-        uses: actions/cache@v2
+        uses: actions/cache@v4
         with:
           path: ${{ env.pythonLocation }}
           key: ${{ env.GHA_DISTRO }}-${{ env.pythonLocation }}-${{ hashFiles('requirements.txt', 'dev-requirements.txt') }}
@@ -44,7 +44,7 @@ jobs:
         with:
           python-version: 3.6
       - name: Cache pip
-        uses: actions/cache@v2
+        uses: actions/cache@v4
         with:
           path: ${{ env.pythonLocation }}
           key: ${{ env.GHA_DISTRO }}-${{ env.pythonLocation }}-${{ hashFiles('requirements.txt', 'dev-requirements.txt') }}