Port CI to Gitea.com (#1)

# Problems
- [x] Some env variables from act itself / act_runner let the tests fail.
- [ ] CI takes too long to clone actions, need to speed up the used act_runner by sparse checkout
    - Runners are reused this speeds up once every runner has ran every job
- [ ] Qemu setup is broken and do not add all platforms like GitHub CI expected`  linux/amd64,linux/amd64/v2,linux/amd64/v3,linux/amd64/v4,linux/arm64,linux/riscv64,linux/ppc64le,linux/s390x,linux/386,linux/mips64le,linux/mips64,linux/loong64,linux/arm/v7,linux/arm/v6` got `linux/amd64,linux/amd64/v2,linux/amd64/v3,linux/amd64/v4,linux/386` without qemu set up
  - Test Disabled
- [x] ACTIONS_RUNTIME_TOKEN needs to be unset
- [ ] Snapshot needs our version of the npm package / patching
  - Test Disabled
- [ ] ACTIONS_RESULTS_URL:http://127.0.0.1:12345/ seems to be a fallback to localhost this is a problem
  - Test Disabled

Reviewed-on: https://gitea.com/actions-oss/act-cli/pulls/1
Co-authored-by: Christopher Homberger <christopher.homberger@web.de>
Co-committed-by: Christopher Homberger <christopher.homberger@web.de>

pkg/artifacts/server_test.go

@@ -249,6 +249,9 @@ func TestArtifactFlow(t *testing.T) {
 	if testing.Short() {
 		t.Skip("skipping integration test")
 	}
+	if _, ok := os.LookupEnv("NO_EXTERNAL_IP"); ok {
+		t.Skip("skipping test because QEMU is disabled")
+	}
 
 	ctx := context.Background()