Revert "Add version as input for docs versioning (#1540)"

This reverts commit eef9525.

Author: hoxbro

.github/workflows/docs.yaml

@@ -17,9 +17,6 @@ on:
         - dryrun
         required: true
         default: dryrun
-    version:
-      description: 'Version tag (required if target is main)'
-      required: false
   schedule:
     - cron: '0 15 * * SUN'