[dev.regabi] cmd/go: copy internal/abi in TestNewReleaseRebuildsStale…

…PackagesInGOPATH

The internal/abi package is used by runtime and needs to be
copied.

Fix longtest builders.

Change-Id: I7a962df3db2c6bf68cc6a7da74b579f381920009
Reviewed-on: https://go-review.googlesource.com/c/go/+/292592
Reviewed-by: Michael Knyszek <mknyszek@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Trust: Cherry Zhang <cherryyz@google.com>
Run-TryBot: Cherry Zhang <cherryyz@google.com>

src/cmd/go/go_test.go

@@ -811,6 +811,7 @@ func TestNewReleaseRebuildsStalePackagesInGOPATH(t *testing.T) {
 	// so that we can change files.
 	for _, copydir := range []string{
 		"src/runtime",
+		"src/internal/abi",
 		"src/internal/bytealg",
 		"src/internal/cpu",
 		"src/math/bits",