BREAKING: remove overload of Deno.test() (#4951)

This commit removes overload of Deno.test() that accepted named
function.

cli/js/lib.deno.ns.d.ts

@@ -57,24 +57,6 @@ declare namespace Deno {
    */
   export function test(t: TestDefinition): void;
 
-  /** Register a test which will be run when `deno test` is used on the command
-   * line and the containing module looks like a test module.
-   * `fn` can be async if required.
-   *
-   *        import {assert, fail, assertEquals} from "https://deno.land/std/testing/asserts.ts";
-   *
-   *        Deno.test(function myTestFunction():void {
-   *          assertEquals("hello", "hello");
-   *        });
-   *
-   *        Deno.test(async function myAsyncTestFunction():Promise<void> {
-   *          const decoder = new TextDecoder("utf-8");
-   *          const data = await Deno.readFile("hello_world.txt");
-   *          assertEquals(decoder.decode(data), "Hello world")
-   *        });
-   **/
-  export function test(fn: () => void | Promise<void>): void;
-
   /** Register a test which will be run when `deno test` is used on the command
    * line and the containing module looks like a test module.
    * `fn` can be async if required.