add unit test and coverage generation

.gitea/workflows/build.yaml

@@ -5,7 +5,8 @@ jobs:
   build:
     runs-on: ubuntu-latest
     steps:
-      - run: echo "Branch ${{ gitea.ref }} will be built for project ${{ gitea.repository }}."
+      - name: Starting action...
+        run: echo "Branch ${{ gitea.ref }} will be built for project ${{ gitea.repository }}."
       - name: Checkout branch
         uses: actions/checkout@v3
       - name: Update package cache
@@ -18,3 +19,7 @@ jobs:
         run: meson setup builddir -Db_coverage=true
       - name: build all targets
         run: ninja -C builddir
+      - name: run unit tests
+        run: ninja -C builddir test
+      - name: calculate coverage
+        run: ninja -C builddir coverage-text