Add regression test

Author: ahejlsberg

tests/cases/compiler/genericIsNeverEmptyObject.ts

@@ -0,0 +1,11 @@
+// @strict: true
+
+// Repro from #29067
+
+function test<T extends { a: string }>(obj: T) {
+    let { a, ...rest } = obj;
+    return { ...rest, b: a };
+}
+
+let o1 = { a: 'hello', x: 42 };
+let o2: { b: string, x: number } = test(o1);