minor symfony#57882 Adjust PR template (OskarStark)

This PR was merged into the 5.4 branch.

Discussion
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Adjust PR template

| Q             | A
| ------------- | ---
| Branch?       | 5.4
| Bug fix?      | no
| New feature?  | no
| Deprecations? | no
| Issues        | --
| License       | MIT

Commits
-------

a2b6378 Adjust PR template

Author: xabbuh

.github/PULL_REQUEST_TEMPLATE.md

@@ -1,6 +1,6 @@
 | Q             | A
 | ------------- | ---
-| Branch?       | 7.2 for features / 5.4, 6.4, 7.0, and 7.1 for bug fixes <!-- see below -->
+| Branch?       | 7.2 for features / 5.4, 6.4, and 7.1 for bug fixes <!-- see below -->
 | Bug fix?      | yes/no
 | New feature?  | yes/no <!-- please update src/**/CHANGELOG.md files -->
 | Deprecations? | yes/no <!-- please update UPGRADE-*.md and src/**/CHANGELOG.md files -->