[management] Add idp timeout env variable (#4647)

Introduced the NETBIRD_IDP_TIMEOUT environment variable to the management service. This allows configuring a timeout for supported IDPs. If the variable is unset or contains an invalid value, a default timeout of 10 seconds is used as a fallback.

This is needed for larger IDP environments where 10s is just not enough time.

management/server/idp/auth0.go

@@ -135,10 +135,11 @@ func NewAuth0Manager(config Auth0ClientConfig, appMetrics telemetry.AppMetrics)
 	httpTransport := http.DefaultTransport.(*http.Transport).Clone()
 	httpTransport.MaxIdleConns = 5
 
-	httpClient := &http.Client{
-		Timeout:   10 * time.Second,
+		httpClient := &http.Client{
+		Timeout:   idpTimeout(),
 		Transport: httpTransport,
 	}
+
 	helper := JsonParser{}
 
 	if config.AuthIssuer == "" {