Error on github pull request populate

[glebk]

Hi,

While trying to use GitHub Pull Request Builder v1.30 with GitHub API Plugin v1.72 we are seeing the following error:

Feb 02, 2016 9:13:02 AM FINEST org.jenkinsci.plugins.ghprb.GhprbPullRequest Running the build
Feb 02, 2016 9:13:02 AM FINEST org.jenkinsci.plugins.ghprb.GhprbPullRequest PR is not null, checking if mergable
Feb 02, 2016 9:13:02 AM SEVERE org.jenkinsci.plugins.ghprb.GhprbPullRequest checkMergeable Couldn't obtain mergeable status.

com.fasterxml.jackson.databind.JsonMappingException: No content to map due to end-of-input
 at [Source: java.io.StringReader@3a506e2d; line: 1, column: 1]
    at com.fasterxml.jackson.databind.JsonMappingException.from(JsonMappingException.java:164)
    at com.fasterxml.jackson.databind.ObjectReader._initForReading(ObjectReader.java:1298)
    at com.fasterxml.jackson.databind.ObjectReader._bindAndClose(ObjectReader.java:1199)
    at com.fasterxml.jackson.databind.ObjectReader.readValue(ObjectReader.java:830)
    at org.kohsuke.github.Requester.parse(Requester.java:492)
    at org.kohsuke.github.Requester._to(Requester.java:236)
    at org.kohsuke.github.Requester.to(Requester.java:210)
    at org.kohsuke.github.GHPullRequest.populate(GHPullRequest.java:205)
    at org.kohsuke.github.GHPullRequest.getMergeable(GHPullRequest.java:170)
    at org.jenkinsci.plugins.ghprb.GhprbPullRequest.checkMergeable(GhprbPullRequest.java:396)
    at org.jenkinsci.plugins.ghprb.GhprbPullRequest.tryBuild(GhprbPullRequest.java:274)
    at org.jenkinsci.plugins.ghprb.GhprbPullRequest.check(GhprbPullRequest.java:150)
    at org.jenkinsci.plugins.ghprb.GhprbRepository.check(GhprbRepository.java:142)
    at org.jenkinsci.plugins.ghprb.GhprbRepository.check(GhprbRepository.java:126)
    at org.jenkinsci.plugins.ghprb.Ghprb.run(Ghprb.java:119)

We are able to verify that the plugins have connectivity and permissions to the pull requests.

Please let me know what additional information I can provide to help debug this.

Thanks!