Function register

register(
    testClassName: string,
    testName: string,
    testFunction: (arg0: Test) => void,
): RegistrationBuilder
Parameters
- testClassName: string
  Name of the class of tests this test should be a part of.
- testName: string
  Name of this specific test.
- testFunction: (arg0: Test) => void
  Implementation of the test function.
Returns RegistrationBuilder
Returns a RegistrationBuilder object where additional options for this test can be specified via builder methods.
Remarks
Registers a new GameTest function. This GameTest will become available in Minecraft via /gametest run [testClassName]:[testName].

Write Privilege
This function can't be called in read-only mode.

This function can be called in early-execution mode.
Example: simpleMobGameTest.ts
```
import { Test, register } from "@minecraft/server-gametest";
import { MinecraftEntityTypes } from "@minecraft/vanilla-data";

function simpleMobGameTest(test: Test) {
  const attackerId = MinecraftEntityTypes.Fox;
  const victimId = MinecraftEntityTypes.Chicken;

  test.spawn(attackerId, { x: 5, y: 2, z: 5 });
  test.spawn(victimId, { x: 2, y: 2, z: 2 });

  test.assertEntityPresentInArea(victimId, true);

  test.succeedWhen(() => {
    test.assertEntityPresentInArea(victimId, false);
  });
}
register("StarterTests", "simpleMobTest", simpleMobGameTest).maxTicks(400).structureName("gametests:mediumglass");
```