Add support for GH Custom Notification Context

Task: #35637
Story: #2006141
Change-Id: Id4bbc73a709a7cd292072ab66666bd647f0514a6

jenkins_jobs/modules/project_multibranch.py

@@ -796,6 +796,10 @@ def github_scm(xml_parent, data):
         discovered initially or a change from the previous revision has been
         detected. (optional)
         Refer to :func:`~build_strategies <build_strategies>`.
+    :arg str notification-context: Change the default GitHub check notification
+        context from "continuous-integration/jenkins/SUFFIX" to a custom text,
+        Requires the :jenkins-wiki:`Github Custom Notification Context SCM
+        Behaviour <Github+Custom+Notification+Context+SCM+Behaviour+Plugin>`.
     :arg dict property-strategies: Provides control over how to build a branch
         (like to disable SCM triggering or to override the pipeline durability)
         (optional)
@@ -980,6 +984,14 @@ def github_scm(xml_parent, data):
     if data.get('build-strategies', None):
         build_strategies(xml_parent, data)
 
+    if data.get('notification-context', None):
+        rshf = XML.SubElement(traits,
+            'org.jenkinsci.plugins.githubScmTraitNotificationContext.'
+            'NotificationContextTrait')
+        XML.SubElement(rshf, 'contextLabel').text = data.get(
+            'notification-context')
+        XML.SubElement(rshf, 'typeSuffix').text = 'true'
+
     # handle the default git extensions like:
     # - clean
     # - shallow-clone

tests/multibranch/fixtures/scm_github_full.xml

@@ -55,6 +55,10 @@
             <jenkins.scm.impl.trait.RegexSCMHeadFilterTrait>
               <regex>(.*/master|.*/release/.*)</regex>
             </jenkins.scm.impl.trait.RegexSCMHeadFilterTrait>
+            <org.jenkinsci.plugins.githubScmTraitNotificationContext.NotificationContextTrait>
+              <contextLabel>jenkins.example.com/my_context</contextLabel>
+              <typeSuffix>true</typeSuffix>
+            </org.jenkinsci.plugins.githubScmTraitNotificationContext.NotificationContextTrait>
             <jenkins.plugins.git.traits.CleanAfterCheckoutTrait>
               <extension class="hudson.plugins.git.extensions.impl.CleanCheckout"/>
             </jenkins.plugins.git.traits.CleanAfterCheckoutTrait>

tests/multibranch/fixtures/scm_github_full.yaml

@@ -15,6 +15,7 @@ scm:
         discover-pr-forks-trust: everyone
         discover-pr-origin: both
         discover-tags: true
+        notification-context: 'jenkins.example.com/my_context'
         property-strategies:
             all-branches:
                 - suppress-scm-triggering: true