Bitbucket Data Center can be configured to reject untrusted build status updates (via build.status.reject-untrusted=true)

Bitbucket Branch Source Plugin currently does not sign the build status using the Jenkins private InstanceIdentity RSA key and does not send the required headers for this trust chain of Bitbucket to work:

• base-url
• BBS-Signature
• BBS-Signature-Algorithm

As a result build-status updates from the plugin fail with the error:
Build status trust chain cannot be verified and the server is configured to reject untrusted build status

Request: adding support for trusted build-status notifications (for Bitbucket Data Center) following the same signing mechanism used by the Atlassian Bitbucket Server Integration plugin.

Potential reference: atlassian-bitbucket-server-integration-plugin/src/main/java/com/atlassian/bitbucket/jenkins/internal/client/ModernBitbucketBuildStatusClientImpl.java at master - jenkinsci/atlassian-bitbucket-server-integration-plugin - GitHub