When trying to process a sync run an error occurs and the job is frozen.
1. The jobserver is communicating with the database and checking for jobs
2. The sync job appears in the queue as expected
3. The job server appears to load the job and then stops. The following error is seen in the jobserver log.
 Error executing synchronization.
[System.Reflection.TargetInvocationException] Exception has been thrown by the target of an invocation.
[System.Net.WebException] The underlying connection was closed: Could not establish trust relationship for the SSL/TLS secure channel.
[System.Security.Authentication.AuthenticationException] The remote certificate is invalid according to the validation procedure.