cmd/go: drop unnecessary Package argument to reportCmd
Now that we've dropped the redundant Package arguments to many
functions, we can see that the Package argument to reportCmd is always
nil. That means we can drop it and always use a.Package.
For #62067.
Change-Id: I2e11e770f495d6f770047993358c76b08204e923
Reviewed-on: https://go-review.googlesource.com/c/go/+/536096
Auto-Submit: Austin Clements <austin@google.com>
Reviewed-by: Bryan Mills <bcmills@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>