Fix galaxy url use everywhere when url is set in config. (#63286)

In addition to trying the configured url (for ex, a migrated
'https://galaxy.ansible.com/') there is an attempt at that
URL with '/api' postpended.

If the extended URL works, update GalaxyAPI.api_server to
use the extended URL. Previously it only used it for finding
the API root info ('available_versions', etc)

lib/ansible/galaxy/api.py

@@ -57,6 +57,10 @@ def g_connect(versions):
                         raise AnsibleError("Tried to find galaxy API root at %s but no 'available_versions' are available on %s"
                                            % (n_url, self.api_server))
 
+                    # Update api_server to point to the "real" API root, which in this case
+                    # was the configured url + '/api/' appended.
+                    self.api_server = n_url
+
                 # Default to only supporting v1, if only v1 is returned we also assume that v2 is available even though
                 # it isn't returned in the available_versions dict.
                 available_versions = data.get('available_versions', {u'v1': u'v1/'})