Java: update change note

Author: Jami Cogswell

java/ql/lib/change-notes/2023-05-05-java-sink-kind-revamp.md

@@ -1,7 +1,7 @@
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 category: minorAnalysis
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-* Updated the following Java sink kind names:
+* Updated the following Java sink kind names. Any custom data extensions will need to be updated accordingly in order to continue working.
   * `sql` to `sql-injection`
   * `url-redirect` to `url-redirection`
   * `xpath` to `xpath-injection`