Update POLICIES.md (#2915)

Fix link to sampleFile.java, which might have been pointing to an older url that no longer works.

Author: shreyasgosavi

POLICIES.md

@@ -51,7 +51,7 @@ References: [[1](https://github.com/exercism/java/issues/177#issuecomment-261291
 >   throw new UnsupportedOperationException("Delete this statement and write your own implementation.");
 >   ```
 >
-> - Exercises of difficulty 5 or higher: copy the StubTemplate.java file (provided [here](https://github.com/exercism/java/tree/main/_template/src/main/java)) and rename it to fit the exercise. For example, for the exercise linked-list the file could be named LinkedList.java. Then either (1) add hints to the hints.md file (which gets merged into the README.md for the exercise) or (2) provide stubs as above for exercises that demand complicated method signatures.
+> - Exercises of difficulty 5 or higher: copy the StubTemplate.java file (provided [here](https://github.com/exercism/java/blob/main/resources/exercise-template/src/main/java/ExerciseName.java)) and rename it to fit the exercise. For example, for the exercise linked-list the file could be named LinkedList.java. Then either (1) add hints to the hints.md file (which gets merged into the README.md for the exercise) or (2) provide stubs as above for exercises that demand complicated method signatures.
 
 References: [[1](https://github.com/exercism/java/issues/178)], [[2](https://github.com/exercism/java/pull/683#discussion_r125506930)], [[3](https://github.com/exercism/java/issues/977)], [[4](https://github.com/exercism/java/issues/1721)]