catch exceptions thrown by sh step running pr-builder.sh

If the pr-builder fails, the sh step running it will throw an exception. This
exception prevents later steps from running. If this exception is raised, we
catch it so the job can properly finish. However, catching the exception will
set the overall job status to sucess, but we can manually set it back to a
failure.

Signed-off-by: Joe Downs <joe@dwns.dev>

Author: Joe-Downs

.ci/community-jenkins/Jenkinsfile

@@ -79,7 +79,16 @@ def prepare_build(build_name, label, build_arg) {
         stage("${build_name}") {
             node(label) {
                 checkout(changelog: false, poll: false, scm: scm)
-                sh "/bin/bash -x .ci/community-jenkins/pr-builder.sh ${build_arg} ompi"
+                // If pr-builder.sh fails, the sh step will throw an exception,
+                // which we catch so that the job doesn't abort and continues on
+                // to other steps - such as cleanup. Because we catch the
+                // exception, we need to tell Jenkins the overall job has
+                // failed.
+                try {
+                    sh "/bin/bash -x .ci/community-jenkins/pr-builder.sh ${build_arg} ompi"
+                } catch (Exception e) {
+                    currentBuild.result = "FAILURE"
+                }
                 cleanWs(notFailBuild: true)
             }
         }