Fix JENKINS-45775 cause jenkins could not proccess pr event trigged by webhook.

use a  private test Bitbucket server ,  create demo team demo project.

In jenkins side create demo job use "Bitbucket team project" all repo branch scanned correct.

other people's pull request create to demo project can not trigger job build at all (webhook config can trigger successful).

When I debug the plugin  i found then problem happens BitbucketSCMSource.java #640

if (originBitbucket instanceof BitbucketCloudApiClient) {
}else{

// the PullRequestSCMHead created here can not match request.include 
//because the fourth param source branch name not match.

}