[JENKINS-64418] Fix duplicate base URL in request to Bitbucket Server

[KalleOlaviNiemitalo]

Commit e4d32d5 (#927 for JENKINS-64418) introduced a bug that duplicates the base URL in some HTTP requests to Bitbucket Server, causing an error like this:

java.io.FileNotFoundException: URL: https://bitbucket.examplehttps://bitbucket.example/rest/api/1.0/projects/DEMO/repos/demo/branches?filterText=master&start=0&limit=200
	at com.cloudbees.jenkins.plugins.bitbucket.impl.client.AbstractBitbucketApi.doRequest
java.io.IOException: Communication error for url: GET https://bitbucket.examplehttps://bitbucket.example/rest/api/1.0/projects/DEMOrepos/demo/branches?filterText=master&start=0&limit=200 HTTP/1.1
	at com.cloudbees.jenkins.plugins.bitbucket.impl.client.AbstractBitbucketApi.doRequest
	at com.cloudbees.jenkins.plugins.bitbucket.impl.client.AbstractBitbucketApi.getRequest
	at com.cloudbees.jenkins.plugins.bitbucket.server.client.BitbucketServerAPIClient.getResource
	at com.cloudbees.jenkins.plugins.bitbucket.server.client.BitbucketServerAPIClient.getSingleBranch
	at com.cloudbees.jenkins.plugins.bitbucket.server.client.BitbucketServerAPIClient.getBranch
	at com.cloudbees.jenkins.plugins.bitbucket.BitbucketSCMSource.retrieve
	at jenkins.scm.api.SCMSource.fetch

The problem is that getSingleBranch prepends this.baseURL to the URI template and calls getResource, which expands the template and prepends this.baseURL to the resulting URL again.

getResource is called only by getSingleTag and getSingleBranch, and both of them include the base URL in the template. Thus, getResource should not prepend it again.

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• Make sure you are requesting to pull a topic/feature/bugfix branch (right side) and not your master branch!
• Ensure that the pull request title represents the desired changelog entry
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[KalleOlaviNiemitalo]

The latest release 933.2.0 was made before the bug was introduced.

[KalleOlaviNiemitalo]

@nfalco79 should I file a separate issue for this even though the bug has not been released yet? Or will the fix go in as part of the JENKINS-64418 implementation?

[nfalco79]

@nfalco79 should I file a separate issue for this even though the bug has not been released yet? Or will the fix go in as part of the JENKINS-64418 implementation?

No needed, you can refer the same jenkins issue. I normally release after 1/2 weeks it works in our production

[KalleOlaviNiemitalo]

The commit title format [JENKINS-XYZ] <Issue Title> that you requested in #940 (comment) feels unsuitable to this, when this PR is not adding a backoff loop.

[nfalco79]

Does matter I will change the title and comment on merge

[KalleOlaviNiemitalo]

Tested that building a branch works OK with commit 539c964.

Didn't test building a tag yet.