Update jenkins/jenkins Docker tag to v2.387.1

This MR contains the following updates:

Package	Type	Update	Change
jenkins/jenkins	ironbank-docker	minor	2.375.3-lts -> 2.387.1-lts
jenkins/jenkins		minor	2.375.3-lts -> 2.387.1-lts
jenkins/jenkins	stage	minor	2.375.3-lts -> 2.387.1-lts

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