Add missing vscode:publish command from package.json.

This command was referenced from the ci-releas.sh script.

Author: olafurpg

package.json

@@ -51,6 +51,7 @@
     },
     "scripts": {
         "vscode:prepublish": "test -f ./syntaxes/Scala.tmLanguage.json",
+        "vscode:publish": "vsce publish --yarn",
         "build": "ts-node src/typescript/GenerateTmLanguageFile.ts > ./syntaxes/Scala.tmLanguage.json"
     }
 }