Explicitly specify vscode.CodeAction

Author: winstliu

src/features/codeActionProvider.ts

@@ -13,7 +13,7 @@ import OptionProvider from '../observers/OptionProvider';
 import { LanguageMiddlewareFeature } from '../omnisharp/LanguageMiddlewareFeature';
 import { buildEditForResponse } from '../omnisharp/fileOperationsResponseEditBuilder';
 
-export default class CodeActionProvider extends AbstractProvider implements vscode.CodeActionProvider {
+export default class CodeActionProvider extends AbstractProvider implements vscode.CodeActionProvider<vscode.CodeAction> {
     private _commandId: string;
 
     constructor(server: OmniSharpServer, private optionProvider: OptionProvider, languageMiddlewareFeature: LanguageMiddlewareFeature) {