misc/cgo/testplugin: fix typo in comment

Change-Id: I7d1a5f6936505dff8f765541b5102dcbcd6ae835
Reviewed-on: https://go-review.googlesource.com/c/go/+/235924
Reviewed-by: Ian Lance Taylor <iant@golang.org>
diff --git a/misc/cgo/testplugin/plugin_test.go b/misc/cgo/testplugin/plugin_test.go
index ab98f61..2875271 100644
--- a/misc/cgo/testplugin/plugin_test.go
+++ b/misc/cgo/testplugin/plugin_test.go
@@ -32,7 +32,7 @@
 }
 
 func testMain(m *testing.M) int {
-	// Copy testdata into GOPATH/src/testarchive, along with a go.mod file
+	// Copy testdata into GOPATH/src/testplugin, along with a go.mod file
 	// declaring the same path.
 
 	GOPATH, err := ioutil.TempDir("", "plugin_test")