refactor: remove redundant type annotation

clients/idms-dialect-support/src/extension.ts

@@ -2,7 +2,7 @@
 // Import the module and reference it with the alias vscode in your code below
 import * as vscode from "vscode";
 
-const mainExtension: string = "BroadcomMFD.cobol-language-support";
+const mainExtension = "BroadcomMFD.cobol-language-support";
 const dialectName = "IDMS";
 
 let unregisterDialect: () => void;