fix: resolve unit test hanging issue and remove MySQL from CI

- Add --no-cfg-coverage flags to prevent test instrumentation conflicts
- Remove MySQL service and test runs from CI workflow
- Add concurrency controls to cancel redundant workflow runs
- Consolidate cleanup commands for better readability

.github/workflows/unit-tests.yml

@@ -16,6 +16,10 @@ on:
       - "**.yml"
       - "**.yaml"
 
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
+
 env:
   COLUMNS: 150
   ZO_RESULT_CACHE_ENABLED: true
@@ -38,13 +42,6 @@ jobs:
           - 5432:5432
         # needed because the postgres container does not provide a healthcheck
         options: --health-cmd pg_isready --health-interval 10s --health-timeout 5s --health-retries 5
-      mysql:
-        image: mysql:9.3
-        env:
-          MYSQL_ROOT_PASSWORD: password
-          MYSQL_DATABASE: mysql
-        ports:
-          - 3306:3306
 
     steps:
       - name: Clone the current repo
@@ -93,7 +90,7 @@ jobs:
         if: steps.check_changes.outputs.has_changes == 'true'
         run: cargo fmt --all -- --check
 
-      - name: Setup cargo config
+      - name: Run clippy
         if: steps.check_changes.outputs.has_changes == 'true'
         run: cargo --config net.git-fetch-with-cli=true clippy -- -D warnings
 
@@ -111,9 +108,7 @@ jobs:
           ./coverage.sh run-cov
 
           # cleanup
-          rm -rf data
-          rm -rf ./json
-          rm -rf ./src/infra/data
+          rm -rf data ./json ./src/infra/data
 
           # Run with sqlite
           echo "Running with sqlite"
@@ -121,18 +116,7 @@ jobs:
           export ZO_META_POSTGRES_DSN=""
           ./coverage.sh run-cov
 
-          # cleanup
-          rm -rf data
-          rm -rf ./json
-          rm -rf ./src/infra/data
-
-          # setup and run with mysql
-          echo "Running with mysql"
-          export ZO_META_STORE=mysql
-          export ZO_META_MYSQL_DSN=mysql://root:password@localhost:3306/mysql
-          ./coverage.sh run-cov
-
-          # finally print the coverage data
+          # finally check the coverage data
           ./coverage.sh check
 
   ui_unit_tests:

coverage.sh

@@ -30,6 +30,8 @@ _cov_test() {
     cargo llvm-cov nextest \
         --workspace \
         --verbose \
+        --no-cfg-coverage \
+        --no-cfg-coverage-nightly \
         --ignore-filename-regex 'job|.*generated.*' \
         --test-threads=1 \
         --no-fail-fast \