feat: improve build performance

Github actions now support dependencies caching.
This should improve the overall build and test time in general

More detail here: https://github.blog/changelog/2021-11-23-github-actions-setup-python-now-supports-dependency-caching/

Authored-by: Vinit Kumar <vinit.kumar@socialschools.nl>
Signed-off-by: Vinit Kumar <vinit.kumar@socialschools.nl>

.github/workflows/test.yml

@@ -38,6 +38,7 @@ jobs:
       uses: actions/setup-python@v2
       with:
         python-version: ${{ matrix.python-version }}
+        cache: 'pip'
     - name: Install dependencies
       run: |
         sudo apt install gettext gcc -y
@@ -89,6 +90,7 @@ jobs:
       uses: actions/setup-python@v2
       with:
         python-version: ${{ matrix.python-version }}
+        cache: 'pip'
     - name: Install dependencies
       run: |
         sudo apt install gettext gcc -y
@@ -129,6 +131,7 @@ jobs:
       uses: actions/setup-python@v2
       with:
         python-version: ${{ matrix.python-version }}
+        cache: 'pip'
     - name: Install dependencies
       run: |
         sudo apt install gettext gcc -y