no-jira: fix NPE in the indexer REST API for statistics if the indexer is disabled
no-jira: fix a NPE if a JMS event try to change the efficiency statement link but it's not initialized
Merge OpenOLAT 9.4 to OpenOLAT default branch with 45d8d1582c3ce1c93e38740f883ee4c0ef682d81
OO-1199: hardened the event handling to handle only the single select element we are interested in