Primarily, this change removes the cmd/ prefix on the go command
counter names. The 'error' counter is changed to 'errors' reflecting
that it's a bucket that contains multiple errors. the switch-exec and
select-exec counters are moved into a 'toolchain' grouping.
For #58894
Change-Id: Id6e0e7a0b4a5e42a0aef04b1210d2bb5256eb6c2
Reviewed-on: https://go-review.googlesource.com/c/go/+/570736 Reviewed-by: Hyang-Ah Hana Kim <hyangah@gmail.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>