refactor(cli): rewrite ops to use ResourceTable2

[bartlomieju]

No description provided.

[piscisaureus]

Looks like https://github.com/denoland/deno/pull/8512/files/8fcb9a496bbadc19dc1c22c226ff17656b286bce#diff-6b4e31d40f717632f8b6eb94b2a0828d3cde3ee6df5197d49e976068f9be33b2 hasn't been addressed.
We also need a test for it, which should roughly do the following:

• Create an UDP socket.
• Start receiving packets on that UDP socket.
• Use the UDP socket to send a packet to itself.
• Verify that the packet has been received.

[piscisaureus]

test (verified to pass w/ deno 1.6.1):

const socket = Deno.listenDatagram({ port: 3500, transport: "udp" });
assert(socket.addr.transport === "udp");
assertEquals(socket.addr.port, 3500);
assertEquals(socket.addr.hostname, "127.0.0.1");

const recvPromise = socket.receive();

const sendBuf = new Uint8Array([1, 2, 3]);
const sendLen = await socket.send(sendBuf, socket.addr);
assertEquals(sendLen, 3);

const [recvBuf, recvAddr] = await recvPromise;
assertEquals(recvBuf.length, 3);
assertEquals(1, recvBuf[0]);
assertEquals(2, recvBuf[1]);
assertEquals(3, recvBuf[2]);

socket.close();

EDIT: pushed the test to this branch.
EDIT: made the test pass for UDP sockets. The equivalent test for UnixDatagram sockets can't be made to pass until we upgrade to Tokio 0.3, but the (ignored) test has been added to net_test.ts.