Document #4120 in release notes

Author: marcphilipp

documentation/src/docs/asciidoc/release-notes/release-notes-5.12.0-M1.adoc

@@ -137,6 +137,9 @@ JUnit repository on GitHub.
   thread dump to `System.out` prior to interrupting a test thread due to a timeout.
 * `TestReporter` now allows publishing files for a test method or test class which can be
   used to include them in test reports, such as the Open Test Reporting format.
+* Auto-registered extensions can now be
+  <<../user-guide/index.adoc#extensions-registration-automatic-filtering, filtered>> using
+  include and exclude patterns that can be specified as configuration parameters.
 
 
 [[release-notes-5.12.0-M1-junit-vintage]]