Avoid calling Team API with an expired token.

Previously, the controller fetched the Oauth token once at start, so eventually the token would expire and the operator could not create new users. This commit makes the operator fetch the token before each call to the Teams API.

pkg/controller/controller.go

@@ -68,12 +68,7 @@ func (c *Controller) initController() {
 		c.logger.Fatalf("Can't register ThirdPartyResource: %s", err)
 	}
 
-	token, err := c.getOAuthToken()
-	if err != nil {
-		c.logger.Errorf("Can't get OAuth token: %s", err)
-	} else {
-		c.config.TeamsAPIClient.OAuthToken = token
-	}
+	c.config.TeamsAPIClient.RefreshTokenAction = c.getOAuthToken
 
 	// Postgresqls
 	clusterLw := &cache.ListWatch{