Adds support for ERB-files

Author: davidwessman

package.json

@@ -18,6 +18,7 @@
     "vscode": "^1.68.0"
   },
   "activationEvents": [
+    "onLanguage:erb",
     "onLanguage:haml",
     "onLanguage:ruby",
     "workspaceContains:Gemfile.lock",

src/extension.ts

@@ -196,6 +196,7 @@ export async function activate(context: ExtensionContext) {
     // responsible for the communication and management of the Ruby subprocess.
     languageClient = new LanguageClient("Syntax Tree", { run, debug: run }, {
       documentSelector: [
+        { scheme: "file", language: "erb" },
         { scheme: "file", language: "haml" },
         { scheme: "file", language: "ruby" },
         { scheme: "file", pattern: "**/Gemfile" },