pubsub: fix package name in go_mod_tidy_hack.go

This will be tagged pubsub/v1.0.1.

Change-Id: Ifd6d6b2fd181872197265fa81b0b904e47edbc2e
Reviewed-on: https://code-review.googlesource.com/c/gocloud/+/44851
Reviewed-by: Alex Hong <hongalex@google.com>
diff --git a/pubsub/go_mod_tidy_hack.go b/pubsub/go_mod_tidy_hack.go
index 376c518..20b8659 100644
--- a/pubsub/go_mod_tidy_hack.go
+++ b/pubsub/go_mod_tidy_hack.go
@@ -16,7 +16,7 @@
 // the resultant binary.
 // +build modhack
 
-package datastore
+package pubsub
 
 // Necessary for safely adding multi-module repo. See: https://github.com/golang/go/wiki/Modules#is-it-possible-to-add-a-module-to-a-multi-module-repository
 import _ "cloud.google.com/go"