Support empty strings in dev-tools package lists

Closes-Bug: #2115000
Change-Id: Ib27428f89b0e3f2865ab1c498f05de741fa49587
Signed-off-by: Pierre Riteau <[email protected]>
(cherry picked from commit 36e7a7b)

Author: priteau

ansible/roles/dev-tools/defaults/main.yml

@@ -15,4 +15,4 @@ dev_tools_packages_system:
   - acl
 
 # List of packages to install.
-dev_tools_packages: "{{ dev_tools_packages_default + dev_tools_packages_extra + dev_tools_packages_system }}"
+dev_tools_packages: "{{ (dev_tools_packages_default + dev_tools_packages_extra + dev_tools_packages_system) | select | list }}"

releasenotes/notes/dev-tools-packages-select-filter-17f432df42762625.yaml

@@ -0,0 +1,7 @@
+---
+fixes:
+  - |
+    Fixes support for empty strings in the ``dev-tools`` package lists. This
+    allows using expressions such as ``{{ 'foo' if os_distribution == 'rocky'
+    else '' }}``.
+    `LP#2115000 <https://bugs.launchpad.net/kayobe/+bug/2115000>`__