Update apt

Author: DavidMStraub

.github/workflows/test.yml

@@ -12,7 +12,7 @@ jobs:
     steps:
       - uses: actions/checkout@v2
       - name: Install Ubuntu dependencies
-        run: sudo apt-get -y install gettext appstream pkg-config libcairo2-dev gir1.2-gtk-3.0 libgirepository1.0-dev libicu-dev libopencv-dev python3-opencv python3-numpy gramps
+        run: sudo apt update && sudo apt-get -y install gettext appstream pkg-config libcairo2-dev gir1.2-gtk-3.0 libgirepository1.0-dev libicu-dev libopencv-dev python3-opencv python3-numpy gramps
       - name: Install Python dependencies
         run: |
           python -m pip install --upgrade pip wheel