Chore: Update test database initialization (#81673)

* streamline initialization of test databases, support on-disk sqlite test db

* clean up test databases

* introduce testsuite helper

* use testsuite everywhere we use a test db

* update documentation

* improve error handling

* disable entity integration test until we can figure out locking error

pkg/services/ngalert/notifier/alertmanager_test.go

@@ -17,8 +17,13 @@ import (
 	"github.com/grafana/grafana/pkg/services/secrets/database"
 	secretsManager "github.com/grafana/grafana/pkg/services/secrets/manager"
 	"github.com/grafana/grafana/pkg/setting"
+	"github.com/grafana/grafana/pkg/tests/testsuite"
 )
 
+func TestMain(m *testing.M) {
+	testsuite.Run(m)
+}
+
 func setupAMTest(t *testing.T) *alertmanager {
 	dir := t.TempDir()
 	cfg := &setting.Cfg{