private Future<Void> closeAndReleaseParent(Channel parentChannel, Throwable cause) {
    return closeAndReleaseParent(parentChannel, cause, parentChannel.eventLoop().newPromise());
  }
Acquire a stream on a connection that has already been initialized. This will return false if the connection cannot have
any more streams allocated, and true if the stream can be allocated.

This will NEVER complete the provided future when the return value is false. This will ALWAYS complete the provided
future when the return value is true.
ambry-network/src/main/java/com/github/ambry/network/http2/Http2MultiplexedChannelPool.java