[Stack Monitoring] Change Messaging to distinguish between different rules of the same rule type

[neptunian]

If, for eg., the user has 2 Disk usage rules and one is set at 10% and the other at 40% but all the nodes are at 90% you will get the same message for both rules. I think we should perhaps include the rule name or include the threshold they set it at:

Same in the action messages:

[elasticmachine]

Pinging @elastic/logs-metrics-ui (Team:logs-metrics-ui)

[elasticmachine]

Pinging @elastic/infra-monitoring-ui (Team:Monitoring)