all: change module to google.golang.org/protobuf

Temporarily remove go.mod, since we can't generate an accurate one until
the corresponding v1 change is submitted.

Change-Id: I1e1ad97f2b455e33f61ffaeb8676289795e47e72
Reviewed-on: https://go-review.googlesource.com/c/protobuf/+/177000
Reviewed-by: Joe Tsai <thebrokentoaster@gmail.com>
diff --git a/internal/legacy/parse.go b/internal/legacy/parse.go
index eac1256..6de9578 100644
--- a/internal/legacy/parse.go
+++ b/internal/legacy/parse.go
@@ -5,8 +5,8 @@
 package legacy
 
 import (
-	"github.com/golang/protobuf/v2/internal/encoding/wire"
-	"github.com/golang/protobuf/v2/internal/fieldnum"
+	"google.golang.org/protobuf/internal/encoding/wire"
+	"google.golang.org/protobuf/internal/fieldnum"
 )
 
 // To avoid a dependency from legacy to descriptor.proto, use a hand-written parser