JSCH workaround for Ubuntu 22.04

Clearly marked workaround code which re-enables ssh-rsa as an
accpeted public key algorithm.

Change-Id: Iabd67c650d03d9b157b45df1481ccd2643a3beb1
Signed-off-by: Mark Beierl <mark.beierl@canonical.com>
diff --git a/jenkins/ci-pipelines/ci_stage_3.groovy b/jenkins/ci-pipelines/ci_stage_3.groovy
index 2c2e008..26f928b 100644
--- a/jenkins/ci-pipelines/ci_stage_3.groovy
+++ b/jenkins/ci-pipelines/ci_stage_3.groovy
@@ -442,6 +442,30 @@
                         }
                     }
                     println('VM is ready and accepting ssh connections')
+
+                    //////////////////////////////////////////////////////////////////////////////////////////////
+                    println('Applying sshd config workaround for Ubuntu 22.04 and old jsch client in Jenkins...')
+
+                    sh( returnStatus: true,
+                        script: "ssh -T -i ${SSH_KEY} " +
+                            "-o StrictHostKeyChecking=no " +
+                            "-o UserKnownHostsFile=/dev/null " +
+                            "ubuntu@${IP_ADDRESS} " +
+                            "'echo HostKeyAlgorithms +ssh-rsa | sudo tee -a /etc/ssh/sshd_config'")
+                    sh( returnStatus: true,
+                        script: "ssh -T -i ${SSH_KEY} " +
+                            "-o StrictHostKeyChecking=no " +
+                            "-o UserKnownHostsFile=/dev/null " +
+                            "ubuntu@${IP_ADDRESS} " +
+                            "'echo PubkeyAcceptedKeyTypes +ssh-rsa | sudo tee -a /etc/ssh/sshd_config'")
+                    sh( returnStatus: true,
+                        script: "ssh -T -i ${SSH_KEY} " +
+                            "-o StrictHostKeyChecking=no " +
+                            "-o UserKnownHostsFile=/dev/null " +
+                            "ubuntu@${IP_ADDRESS} " +
+                            "'sudo systemctl restart sshd'")
+                    //////////////////////////////////////////////////////////////////////////////////////////////
+
                 } // stage("Spawn Remote VM")
 
 ///////////////////////////////////////////////////////////////////////////////////////