Fix broken tempest-tox-plugin-sanity-check job

tempest-tox-plugin-sanity-check job is broken due to
'x/networking-cisco failing plugin. Plugin is brokken
after the below change
- https://review.opendev.org/c/x/networking-cisco/+/969038

Fixing the job by blacklist the 'x/networking-cisco plugin.

Change-Id: I156d3a682f697c6d0ad37451aacfd99816d89bc7
Signed-off-by: Ghanshyam Maan <gmaan.os14@gmail.com>
diff --git a/tools/generate-tempest-plugins-list.py b/tools/generate-tempest-plugins-list.py
index 0690d57..a22e8a4 100644
--- a/tools/generate-tempest-plugins-list.py
+++ b/tools/generate-tempest-plugins-list.py
@@ -83,6 +83,9 @@
     # in this plugin was 7 years ago.
     # https://opendev.org/airship/tempest-plugin
     'airship/tempest-plugin'
+    # It is broken by the below change:
+    # https://review.opendev.org/c/x/networking-cisco/+/969038
+    'x/networking-cisco'
 ]
 
 url = 'https://review.opendev.org/projects/'