Fix mergify (#3388)

* Update mergify

* encapsulate regex pattern in quotes
to avoid this
https://github.com/ruffsl/navigation2/pull/11/checks?check_run_id=10980552759

* Drop any colons
to avoid yaml issues

Author: ruffsl

.github/mergify.yml

@@ -31,7 +31,7 @@ pull_request_rules:
       - merged
     actions:
       delete_head_branch:
- 
+
   - name: ask to resolve conflict
     conditions:
       - conflict
@@ -48,7 +48,7 @@ pull_request_rules:
     actions:
         comment:
           message: |
-            @{{author}}, all pull requests must be targeted towards the `main` development branch. 
+            @{{author}}, all pull requests must be targeted towards the `main` development branch.
             Once merged into `main`, it is possible to backport to @{{base}}, but it must be in `main`
             to have these changes reflected into new distributions.
 
@@ -61,19 +61,19 @@ pull_request_rules:
     actions:
         comment:
           message: |
-            @{{author}}, your PR has failed to build. Please check CI outputs and resolve issues. 
+            @{{author}}, your PR has failed to build. Please check CI outputs and resolve issues.
             You may need to rebase or pull in `main` due to API changes (or your contribution genuinely fails).
 
   - name: Removed maintainer checklist
     conditions:
       - and:
-        - "-body~=(?m)^For Maintainers:"
+        - body-raw~=^#### For Maintainers
         - author!=SteveMacenski
         - author!=mergify
     actions:
         comment:
           message: |
-            @{{author}}, please properly fill in PR template in the future. @stevemacenski, use this instead. 
+            @{{author}}, please properly fill in PR template in the future. @stevemacenski, use this instead.
             - [ ] Check that any new parameters added are updated in navigation.ros.org
             - [ ] Check that any significant change is added to the migration guide
             - [ ] Check that any new features **OR** changes to existing behaviors are reflected in the tuning guide