cmd/go/testdata/script: disable build_plugin_reproducible on darwin

It's broken with the latest XCode versions, and is also already disabled
on darwin builders. Disable the test to get go test cmd/go working on
local builds again.

For #64947

Change-Id: I5a4b46cf23cbe887df4903f90b54cd2225f51233
Reviewed-on: https://go-review.googlesource.com/c/go/+/584937
Reviewed-by: Dmitri Shuralyov <[email protected]>
LUCI-TryBot-Result: Go LUCI <[email protected]>
Reviewed-by: Dmitri Shuralyov <[email protected]>

Author: matloob

src/cmd/go/testdata/script/build_plugin_reproducible.txt

@@ -2,12 +2,10 @@
 [short] skip
 [!cgo] skip '-buildmode=plugin requires external linking'
 
-# This test has problems when run on the LUCI darwin longtest builder,
-# which uses a more contemporary Xcode version that is unfriendly to
-# reproducible builds (see issue #64947 for the gory details). Note
-# that individual developers running "go test cmd/go" on Darwin may
-# still run into failures depending on their Xcode version.
-[GOOS:darwin] [go-builder] skip
+# This test has problems when run on darwin, when using a more
+# contemporary Xcode version that is unfriendly to reproducible builds
+# (see issue #64947 for the gory details).
+[GOOS:darwin] skip
 
 go build -trimpath -buildvcs=false -buildmode=plugin -o a.so main.go
 go build -trimpath -buildvcs=false -buildmode=plugin -o b.so main.go