Add OIDC integration tests

* Port OIDC integration tests to v2

* Move Tailscale old versions to TS2019 list

* Remove Alpine Linux container

* Updated changelog

* Releases: use flavor to set the tag suffix

* Added more debug messages in OIDC registration

* Added more logging

* Do not strip nodekey prefix on handle expired

* Updated changelog

* Add WithHostnameAsServerURL option func

* Reduce the number of namespaces and use hsic.WithHostnameAsServerURL

* Linting fix

* Fix linting issues

* Wait for ready outside the up goroutine

* Minor change in log message

* Add prefix to env var

* Remove unused env var

Co-authored-by: Juan Font <juan.font@esa.int>
Co-authored-by: Steven Honson <steven@honson.id.au>
Co-authored-by: Kristoffer Dalby <kristoffer@dalby.cc>

integration/hsic/hsic.go

@@ -104,6 +104,17 @@ func WithTestName(testName string) Option {
 	}
 }
 
+func WithHostnameAsServerURL() Option {
+	return func(hsic *HeadscaleInContainer) {
+		hsic.env = append(
+			hsic.env,
+			fmt.Sprintf("HEADSCALE_SERVER_URL=http://%s:%d",
+				hsic.GetHostname(),
+				hsic.port,
+			))
+	}
+}
+
 func New(
 	pool *dockertest.Pool,
 	network *dockertest.Network,