Add RabbitMQ single active consumer argument

[DropSnorz]

Description

Added a new RabbitMQ subscription argument to enable Single Active Consumer (x-single-active-consumer)

Usage with declarative subscription

apiVersion: dapr.io/v2alpha1
kind: Subscription
metadata:
  name: orders
spec:
  topic: orders
  routes:
    default: /orders
  pubsubname: orderpubsub
  metadata:
    queueName: "foo-queue-quorum"
    queueType: quorum
    singleActiveConsumer: "true"
scopes:
- order-processor-sdk

Issue reference

We strive to have all PR being opened based on an issue, where the problem or feature have been discussed prior to implementation.

Please reference the issue this PR will close: #3120

Checklist

Please make sure you've completed the relevant tasks for this PR, out of the following list:

• Code compiles correctly
• Created/updated tests
• Extended the documentation / Created issue in the https://github.com/dapr/docs/ repo: dapr/docs#[issue number]

[berndverst]

You need to actually publish a message after this, then assert that the message was received and the overall messageCount has been increased.

[DropSnorz]

Test function updated.

[berndverst]

Do not use strconv.ParseBool instead use our preferred method from package dapr/kit/utils called IsTruthy https://github.com/dapr/kit/blob/106329e5839f70f3234b9f49b7dabff0247c0a90/utils/strings.go#L23

That will allow a lot more values to be used to express the "true" / on state.

[DropSnorz]

Thanks for highlighting this, the code is far more readable this way 👍

[berndverst]

A few small changes / additions, then we can merge this.

[yaron2]

@DropSnorz Thanks for this PR! Please open a docs issue in dapr/docs to update the RabbitMQ pub/sub spec with this setting.