cmd/covdata: close cpu and mem profile
Change-Id: Iaf14989eb2981f724c4091f992ed99687ce3a60e
GitHub-Last-Rev:
6e6c82bb8fba5c32c24eafb50eec6751a93d09f9
GitHub-Pull-Request: golang/go#66852
Reviewed-on: https://go-review.googlesource.com/c/go/+/579255
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
Reviewed-by: Emmanuel Odeke <emmanuel@orijtech.com>
Reviewed-by: Than McIntosh <thanm@google.com>
Auto-Submit: Than McIntosh <thanm@google.com>