During the perfscale work to prepare for selectable etcd db size, it seems that the etcd liveness probes are too low for etcd database size larger than 8 gb

For instance, during a defrag operation, which is a blocking operation, a liveness probe will definitely fails

important consideration: https://docs.google.com/document/d/1BuIvDaTG-GCPWpiJDHYv-sxyEGyE_vS3BC_quP-qPqw/edit?tab=t.0#heading=h.3g190z8b529d 

ref 

metrics and slides: https://docs.google.com/presentation/d/10wbAZAetTRQlXgUcqdmKaKDK7UxsJdB0DjDgSOsUk3M/edit#slide=id.g2cdb013e9b6_0_1493