proto: Add `extend` keyword (#45413)

Zachiah Sawyer created 1 week ago

Closes #45385

Release Notes:
- Add extend keyword to proto

Change summary

extensions/proto/languages/proto/highlights.scm | 1 +
1 file changed, 1 insertion(+)

Detailed changes

extensions/proto/languages/proto/highlights.scm

@@ -9,6 +9,7 @@
   "returns"
   "message"
   "enum"
+  "extend"
   "oneof"
   "repeated"
   "reserved"