Use upstream prometheus-memcached-exporter for test

Author: seunghun1ee

etc/kayobe/kolla.yml

@@ -142,10 +142,10 @@ kolla_sources:
     type: git
     location: https://github.com/prometheus/prometheus.git
     reference: v2.54.1
-  prometheus-memcached-exporter:
-    type: git
-    location: https://github.com/prometheus/memcached_exporter.git
-    reference: v0.14.4
+  # prometheus-memcached-exporter:
+  #   type: git
+  #   location: https://github.com/prometheus/memcached_exporter.git
+  #   reference: v0.14.4
 
 ###############################################################################
 # Kolla image build configuration.