Update github PR template

Author: Jannik Zschiesche

.github/pull_request_template.md

@@ -1,10 +1,10 @@
 | Q             | A
-| ------------- | ---
-| Bug fix?      | yes/no
-| Improvement?  | yes/no <!-- improves an existing feature, not adding a new one --> 
-| New feature?  | yes/no <!-- don't forget to update CHANGELOG.md -->
-| BC breaks?    | no
-| Deprecations? | yes/no <!-- don't forget to update UPGRADE.md and CHANGELOG.md -->
-| Docs PR       | **missing** <!-- insert URL here -->
+| ------------- | --------------------------------------------------------------------- |
+| BC breaks?    | yes/no                                                                |
+| New feature?  | yes/no <!-- don't forget to update CHANGELOG.md -->                   |
+| Improvement?  | yes/no <!-- improves an existing feature, not adding a new one -->    |
+| Bug fix?      | yes/no                                                                |
+| Deprecations? | yes/no <!-- don't forget to update UPGRADE.md and CHANGELOG.md -->    |
+| Docs PR       | **missing** <!-- insert URL here -->                                  |
 
 <!-- describe your changes below -->