[CI] Optimise irrelevant files

Certain files need not trigger extra jobs.

Also ensure special chars are properly escaped (regexp syntax).

Change-Id: I32cb7f4fcf0cabba49adc3d73cbe42d9db9d0150

zuul.d/base.yaml

@@ -17,10 +17,15 @@
     timeout: 1800
     irrelevant-files:
       - ^.*\.rst$
-      - ^doc/.*
-      - ^releasenotes/.*
-      - ^setup.cfg$
-      - ^tox.ini$
+      - ^doc/
+      - ^releasenotes/
+      - ^setup\.cfg$
+      - ^setup\.py$
+      - ^tenks/
+      - ^test-requirements\.txt$
+      - ^tests/
+      - ^tox\.ini$
+      - ^zuul\.d/
 
 - job:
     name: tenks-deploy-teardown-ovs-bios-base

zuul.d/jobs.yaml

@@ -6,6 +6,12 @@
     parent: openstack-tox
     vars:
       tox_envlist: alint
+    irrelevant-files:
+      - ^.*\.rst$
+      - ^doc/
+      - ^releasenotes/
+      - ^tests/
+      - ^zuul\.d/
 
 - job:
     name: tenks-deploy-teardown-ovs-bios-centos8s