Remove querier.at-modifier-enabled flag (#6157) #9670

Job	Run time
lint	4m 9s
CodeQL	7m 2s
build	4m 3s
test	15m 6s
integration-configs-db	2m 42s
integration (requires_docker)	6m 27s
integration (integration_alertmanager)	4m 29s
integration (integration_backward_compatibility)	9m 31s
integration (integration_memberlist)	8m 11s
integration (integration_querier)	12m 32s
integration (integration_ruler)	4m 37s
integration (integration_query_fuzz)	2m 48s
deploy_website	59s
deploy	2m 5s
	1h 24m 41s

Provide feedback