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>

tests/integration/api_packages_goproxy_test.go

@@ -15,6 +15,7 @@ import (
 	"forgejo.org/models/packages"
 	"forgejo.org/models/unittest"
 	user_model "forgejo.org/models/user"
+	"forgejo.org/modules/test"
 	"forgejo.org/tests"
 
 	"github.com/stretchr/testify/assert"
@@ -88,12 +89,12 @@ func TestPackageGo(t *testing.T) {
 			AddBasicAuth(user.Name)
 		MakeRequest(t, req, http.StatusConflict)
 
-		time.Sleep(time.Second)
-
 		content = createArchive(map[string][]byte{
 			packageName + "@" + packageVersion2 + "/go.mod": []byte(goModContent),
 		})
 
+		test.SleepTillNextSecond()
+
 		req = NewRequestWithBody(t, "PUT", url+"/upload", bytes.NewReader(content)).
 			AddBasicAuth(user.Name)
 		MakeRequest(t, req, http.StatusCreated)