build: reset embedder string to "-node.0"

PR-URL: nodejs#44741
Reviewed-By: Ben Noordhuis <info@bnoordhuis.nl>
Reviewed-By: Jiawen Geng <technicalcute@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>

Author: targos

common.gypi

@@ -36,7 +36,7 @@
 
     # Reset this number to 0 on major V8 upgrades.
     # Increment by one for each non-official patch applied to deps/v8.
-    'v8_embedder_string': '-node.12',
+    'v8_embedder_string': '-node.0',
 
     ##### V8 defaults for Node.js #####