Update jenkins-howto.markdown

adding reference to the jenkins parameters

docs/pages/howto/jenkins-howto.markdown

@@ -35,3 +35,6 @@ You can find "**Rerun in Grinder**" links near the top of the Jenkins job that f
               - Optionally, if test requires arguments, CUSTOM_TARGET=-test=<stf_test_class_name>  -test-args="x=a,y=b" (e.g. CUSTOM_TARGET=-test=MathLoadTest -test-args="workload=math,timeLimit=5m")
 
 * Note : `<stf_test_class_name>` should be the name of the STF class to run, not a Playlist target name. For example, if you want to re-run [ClassLoadingTest_5m](https://github.com/adoptium/aqa-tests/blob/517467de209aae47db938d4d2b58f45727912322/system/otherLoadTest/playlist.xml#L57), using system_custom, you can simply copy the last portion of the command line from the playlist (e.g. `-test=ClassloadingLoadTest -test-args="timeLimit=5m"`) for CUSTOM_TARGET.
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+## References
+Exhaustive list of all Adoptium Jenkins parameters with explanations can be found at the [Reference Documentation for Jenkins Test Jobs page](../reference/jenkins-jobs-reference.markdown).