pull_request_template tell about rules

Signed-off-by: Jan Kowalleck <[email protected]>

Author: jkowalleck

.github/pull_request_template.md

@@ -4,6 +4,8 @@ Thank you for taking the time to develop and contribute a core enhancement or fi
 We kindly request that you create pull requests only for things that have been discussed in a ticket first; exceptions may be made for spelling or grammar fixe.
 Please have the related ticket/issue ID ready. 
 If there is none, feel free to create a new ticket: https://github.com/CycloneDX/specification/issues/new/choose
+
+Read more about the process here: https://cyclonedx.org/participate/standardization-process/#working-model
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