mitaka-eol: Remove trusty linters job

Remove trusty from linters-job job-group, no user of the group needs the
trusty job.

Change-Id: Ice3c127af2ade31e618566717bfec0055a875928

jenkins/jobs/misc.yaml

@@ -71,8 +71,6 @@
 
 - job-group:
     name: linters-jobs
-    node:
+    node: ubuntu-xenial
-      - ubuntu-trusty
-      - ubuntu-xenial
     jobs:
       - 'gate-{name}-linters-{node}'

jenkins/jobs/projects.yaml

@@ -8737,6 +8737,8 @@
             - ubuntu-trusty
             - ubuntu-xenial
       - linters-jobs
+      - 'gate-{name}-linters-{node}':
+          node: ubuntu-trusty
       - gate-{name}-requirements
 
 - project: