Use shared zuul stx-tox-linters

Previous commit defined a local zuul job to run tox linters. That job
was badly named, as the names are supposed to be globally-unique.

Solution: remove local job definition and call stx-tox-linters defined
by the Depends-On review.

Story: 2011326
Task: 51549

Depends-On: https://review.opendev.org/c/starlingx/zuul-jobs/+/939454

Change-Id: Id85a4cb464badaf648167dcf60a4874bcd4b2c82
Signed-off-by: Davlet Panech <davlet.panech@windriver.com>

.zuul.yaml

@@ -2,21 +2,14 @@
 - project:
     check:
       jobs:
-        - local-tox-linters
+        - stx-tox-linters
     gate:
       jobs:
-        - local-tox-linters
+        - stx-tox-linters
     post:
       jobs:
         - stx-helm-charts-upload-git-mirror
 
-- job:
-    name: local-tox-linters
-    parent: openstack-tox-linters
-    description: |
-      Run Tox linters on debian-bullseye
-    nodeset: debian-bullseye
-
 - job:
     name: stx-helm-charts-upload-git-mirror
     parent: upload-git-mirror