{Core} az login: Remove the extra linebreak from warning message (#15792)

src/azure-cli-core/azure/cli/core/_profile.py

@@ -1283,7 +1283,7 @@ def _get_authorization_code_worker(authority_url, resource, results):
 
     # Emit a warning to inform that a browser is opened.
     # Only show the path part of the URL and hide the query string.
-    logger.warning("The default web browser has been opened at %s. Please continue the login in the web browser.\n"
+    logger.warning("The default web browser has been opened at %s. Please continue the login in the web browser. "
                    "If no web browser is available or if the web browser fails to open, use device code flow "
                    "with `az login --use-device-code`.", url.split('?')[0])