[improvement] Add prefix_filter option for telemetry

[stevenscg]

Consul has the "prefix_filter" option to allow filtering of the telemetry, which is great for controlling costs and noise.

We use a hosted metrics provider that bills on the number of unique metrics streams submitted.

There are some telemetry items like vault.route.* that we don't use right now and it would be ideal to not have to pay for those until or unless we need them.

[pmmukh]

This change has been added in #12025