Allow passing array of messages to send_messages

[farski]

I can't come up with a good reason why this would be the intended behavior, so I think it's a bug.

If a set of messages is passed to a queue like queue.send_messages(batch), where batch is:

[
    {
        message_body: "foo",
        delay_seconds: 1,
        message_attributes: {...}
    }, {
        message_body: "foo",
        delay_seconds: 1,
        message_attributes: {...}
    }
]

the messages are being corrupted before they actually get sent by send_message_batch on the client.

When sanitize_messages! tries to reformat the value from an Array to a Hash that is properly wrapped and ID'd, it doesn't take into account that the members of the array may be hashes. When hashes like in the example are used, the entire hash ends up getting serialized and shoved into message_body.

This change properly maintains the messages and adds an index, or behaves the old way if a string body is all that's getting passed in.

[houndci-bot]

Prefer single-quoted strings when you don't need string interpolation or special symbols.

[phstc]

Thanks @farski. Before merging it, could you review houndci feedbacks?

[farski]

@phstc Fixed a couple things. Line length in specs doesn't seem like a priority, but I can try to fix it if you'd prefer.

[phstc]

Added to master 🍻