Aurora cluster endpoint detection fails when time_zone doesn't match system_time_zone

The query to find cluster endpoints filters on a last update time. It uses the system_time_zone to create a string of the current time, but the query operates based on the time_zone parameter. In our case, the system_time_zone is UTC and time_zone is US/Central. This results in no endpoints being returned.

Could probably fix by using the time_zone server data parameter or using a time function in the query.