CI: Fix documentation jobs

The documentation jobs (including build-openstack-deploy-guide) are
broken due to the migration to Ubuntu Noble [1]. Fix by installing pcre
via bindep.txt.

Adding bindep.txt to irrelevant-files since it's only used in docs job.

[1] https://lists.openstack.org/archives/list/openstack-discuss@lists.openstack.org/thread/JOMDY26TCW7OX3NXRGOYQCIDXNNJ4E25/

Change-Id: Ie12da610e7ddd100e8b881a06598d94b7a6f43b0

bindep.txt

@@ -0,0 +1,9 @@
+# This is a cross-platform list tracking distribution packages needed for
+# install and tests; see https://docs.opendev.org/opendev/bindep/latest/ for
+# additional information.
+# NOTE(mnasiadka): Currently added to irrelevant-files due to usage only
+#                  in docs job - if usage is extended - needs removal from
+#                  there.
+
+libpcre3-dev [platform:dpkg doc]
+pcre-devel [platform:rpm doc]

zuul.d/base.yaml

@@ -48,6 +48,7 @@
       - openstack/requirements
     irrelevant-files:
       - ^.*\.rst$
+      - ^bindep.txt$
       - ^doc/.*
       - ^releasenotes/.*$
       - ^deploy-guide/.*$