Update planning_5.0.md

Author: mportuga

planning_5.0.md

@@ -15,7 +15,7 @@ Before moving to the new version of Angular, it is in our best interest to updat
 Not all of the tasks here are absolutely necessary for the update, but they should help with a smoother transition to the new version and provide an improved experience for consumers of the grid.
 
 - [ ] Update dev dependencies to the latest versions (MUST)
-- [ ] Merge/decline all outstanding Pull Requests (MUST)
+- [x] Merge/decline all outstanding Pull Requests (MUST)
 - [ ] Clean up issues board of all non-issues, i.e. questions or issues for older versions that are no longer reproducible
 - [ ] Update UI-Grid build system to publish multiple files separated by features, i.e. issue #5802 (MUST)
 - [ ] Update UI-Grid styles to modernize it a bit, i.e. issue #3210