Remove label brackets (use default behaviour) for FXP and SP3 projects (#638)

* FXP: Use default behaviour (no brackets) for labels

* SP3: Use default behaviour (no brackets) for labels

---------

Co-authored-by: Mathieu Leplatre <[email protected]>

Author: davehunt

config/config.prod.yaml

@@ -158,7 +158,6 @@
         - sync_whiteboard_labels
       comment:
         - create_comment
-    labels_brackets: both
     status_map:
       UNCONFIRMED: Backlog
       NEW: Backlog
@@ -295,7 +294,6 @@
         - sync_whiteboard_labels
       comment:
         - create_comment
-    labels_brackets: both
     status_map:
       UNCONFIRMED: To Do
       NEW: To Do