Update jenkins/jenkins Docker tag to v2.379

This MR contains the following updates:

Package	Type	Update	Change
jenkins/jenkins	ironbank-docker	minor	2.378-jdk11 -> 2.379-jdk11
jenkins/jenkins		minor	2.378 -> 2.379
jenkins/jenkins	stage	minor	2.378-jdk11 -> 2.379-jdk11

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