Ignore nightly build files for lint job

In the future, we will work with files related to the nightly builds.
This CL adds those files to the irrelevant-files list under the
translateselectedtext-lint job so changes to those do not trigger this
job, since it is unnecessary.

Bug: translateselectedtext:10
Change-Id: I8c19d742ceccefdf608333ff79fdf2b318455b07
diff --git a/.zuul.yaml b/.zuul.yaml
index c7094b7..5bf22b4 100644
--- a/.zuul.yaml
+++ b/.zuul.yaml
@@ -16,6 +16,8 @@
       - "docs/.*"
       - "OWNERS"
       - "README.md"
+      - "roles/cws-publish/*"
+      - "playbooks/nightly-build/*"
 
 - project:
     check: