[JENKINS-76231] Fix NullPointerException when Content-Type header is missing#219

MarkEWaite merged 2 commits intojenkinsci:masterjenkinsci/http-request-plugin:masterfrom

Fluder-Paradyne:fix-null-resp-errFluder-Paradyne/http-request-plugin:fix-null-resp-errCopy head branch name to clipboard