Master should not require a restart to find Agent certificates in truststore

Current Situation

• If an Agent is added to the JobScheduler environment and the connection to the Agent is secured by use of the HTTPS protocol, then this requires to add the Agent's public certificate to the Master's truststore.
• However, the Master reads the truststore on start-up only, and Agent certificates that are added to the truststore later on are not found during the lifetime of a Master run.
• This situation is not good for users who operate hundreds of Agents and have to add/renew certificates more often. Forcing a restart of the Master breaks ongoing operations.

Desired Behavior

• The JobScheduler Masterr should read the truststore when accessing an Agent.
• This should allow to add/replace certificates in the truststore on-the-fly without any need to restart the Master in order to apply new/changed certificates.