chore: QoL improvements to tests (#7917)

- Use mock helper functions, instead of home-brew solutions.
- Disable cron jobs that are not important to be run during integration tests and might even interfere.
- Avoid sleeping unnecessary, if there's some requirement then sleep or retry until that requirement is met.
- Avoid trying to deliver webhooks that will always result in a failure.

Reviewed-on: https://codeberg.org/forgejo/forgejo/pulls/7917
Reviewed-by: Michael Kriese <michael.kriese@gmx.de>
Co-authored-by: Gusted <postmaster@gusted.xyz>
Co-committed-by: Gusted <postmaster@gusted.xyz>

modules/auth/openid/discovery_cache_test.go

@@ -23,7 +23,7 @@ func (s *testDiscoveredInfo) OpLocalID() string {
 }
 
 func TestTimedDiscoveryCache(t *testing.T) {
-	dc := newTimedDiscoveryCache(1 * time.Second)
+	dc := newTimedDiscoveryCache(100 * time.Millisecond)
 
 	// Put some initial values
 	dc.Put("foo", &testDiscoveredInfo{}) // openid.opEndpoint: "a", openid.opLocalID: "b", openid.claimedID: "c"})
@@ -41,7 +41,7 @@ func TestTimedDiscoveryCache(t *testing.T) {
 	}
 
 	// Sleep one second and try retrieve again
-	time.Sleep(1 * time.Second)
+	time.Sleep(100 * time.Millisecond)
 
 	if di := dc.Get("foo"); di != nil {
 		t.Errorf("Expected a nil, got a result")