test: `pubsub` > `retry` seems flaky

[Yuki Tanaka]

    retry ... FAILED(1s)
error: ConnectionReset: Connection reset by peer (os error 104)
            const rr = await this.#rd.read(this.#buf.subarray(this.#w));
                 ^
          at async read (deno:ext/net/01_net.js:28:19)
          at async BufReader.#fill (https://deno.land/std@0.149.0/io/buffer.ts:323:18)
          at async BufReader.peek (https://deno.land/std@0.149.0/io/buffer.ts:654:9)
          at async readReply (file:///home/runner/work/redis/redis/protocol/reply.ts:13:15)
          at async RedisConnection.sendCommand (file:///home/runner/work/redis/redis/connection.ts:111:19)
          at async RedisConnection.reconnect (file:///home/runner/work/redis/redis/connection.ts:183:7)
          at async RedisSubscriptionImpl.receive (file:///home/runner/work/redis/redis/pubsub.ts:118:11)
          at async Promise.all (index 1)
          at async Object.<anonymous> (file:///home/runner/work/redis/redis/tests/commands/pubsub.ts:125:5)
          at async Function.runTest (https://deno.land/std@0.149.0/testing/_test_suite.ts:358:7)

https://github.com/denodrivers/redis/runs/7499043692?check_suite_focus=true