doc: claim ABI version for Electron 18

PR-URL: #40768
Reviewed-By: Richard Lau <rlau@redhat.com>
Reviewed-By: Rich Trott <rtrott@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Voltrex <mohammadkeyvanzade94@gmail.com>
Reviewed-By: Tobias Nießen <tniessen@tnie.de>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: James M Snell <jasnell@gmail.com>

doc/abi_version_registry.json

@@ -1,5 +1,6 @@
 {
   "NODE_MODULE_VERSION": [
+    { "modules": 103,"runtime": "electron", "variant": "electron",             "versions": "18" },
     { "modules": 102,"runtime": "node",     "variant": "v8_9.5",               "versions": "17.0.0" },
     { "modules": 101,"runtime": "electron", "variant": "electron",             "versions": "17" },
     { "modules": 100,"runtime": "node",     "variant": "v8_9.4",               "versions": "17.0.0-pre" },