Enable doc job to run on -rc tags.

Author: svekars

.github/workflows/doc-build.yml

@@ -8,6 +8,7 @@ on:
       - release/*
     tags:
       - v[0-9]+.[0-9]+.[0-9]+
+      - v[0-9]+.[0-9]+.[0-9]+-rc[0-9]+
   workflow_dispatch:
   schedule:
     - cron: '0 0 * * *'