fix(dts): Deno.ChildProcess actually implements AsyncDisposable

[magurotuna]

deno/runtime/js/40_process.js

Lines 324 to 331 in 2941dd7

	async [SymbolAsyncDispose]() {
	try {
	ops.op_spawn_kill(this.#rid, "SIGTERM");
	} catch {
	// ignore errors from killing the process (such as ESRCH or BadResource)
	}
	await this.#status;
	}

As seen above, what Deno.ChildProcess actually implements is AsyncDisposable, but the type declaration says it's Disposable. This PR fixes the type declaration to match the actual implementation.

[littledivy]

LGTM