[Bindings] Documents direction Metadata Field (Part 2)

[msfussell]

What content needs to be created or modified?
Adding more detail to this PR #3588 (comment)

Describe the solution you'd like
It should be made clear in the docs that it is strongly suggested to provide a "direction" on all bindings. This was only made optional since it would have been a breaking change. As a result

1. All binding examples should include direction property
2. The current direction information here needs to be updated https://docs.dapr.io/reference/api/bindings_api/#binding-direction-optional to say this.
3. In the binding overview https://docs.dapr.io/developing-applications/building-blocks/bindings/bindings-overview/ point to the directions setting in the API topic with a read about binding direction here, comment
4. Update https://docs.dapr.io/developing-applications/building-blocks/bindings/howto-triggers/ to say specify an input direction.
5. Update https://docs.dapr.io/developing-applications/building-blocks/bindings/howto-bindings/ to say specify an output direction.
6. Update https://docs.dapr.io/getting-started/quickstarts/bindings-quickstart/ in to add direction in the examples.
   Quickstart update tracked here Update the Bindings Quickstart to add "direction" property into the component Yaml files quickstarts#886