docs: Fix license link in PR template (#907)

Author: mtrezza

.github/pull_request_template.md

@@ -2,7 +2,7 @@
 ## Pull Request
 
 - Report security issues [confidentially](https://github.com/parse-community/Parse-SDK-Flutter/security/policy).
-- Any contribution is under this [license](https://github.com/parse-community/parse-server/blob/master/LICENSE).
+- Any contribution is under this [license](https://github.com/parse-community/Parse-SDK-Flutter/blob/master/LICENSE).
 - Link this pull request to an [issue](https://github.com/parse-community/Parse-SDK-Flutter/issues?q=is%3Aissue).
 
 ## Issue