add extra completion test

Author: Andarist

tests/cases/fourslash/completionsObjectLiteralInferenceSourceInPartiallyAnnotatedSignature1.ts

@@ -0,0 +1,15 @@
+/// <reference path="fourslash.ts" />
+
+// @strict: true
+// @lib: esnext
+
+//// declare function registerPlugin<Opt extends Record<string, any>>(
+////   callback: (app: any, options: Opt) => void,
+////   opts: NoInfer<Opt>,
+//// ): Promise<void>;
+////
+//// registerPlugin((app, opts: { something: string }) => {}, {
+////   /*1*/
+//// });
+
+verify.completions({ marker: "1", includes: [`something`] });