Pub Sub Binders for Spring Cloud Stream Template

[dwij2812]

Reason/Context

• Google Cloud Pub/Sub is widely used in the industry.
• AsyncAPI 2.6.0 introduced Google Pub/Sub Bindings but the generators still do not support it as a binder.

Description

• Integrating Pub/Sub with Spring Cloud Templates is easy as Google already has the cloud stream integration.
• Adding the pubsub binders will enable lots of teams and enterprises to adopt Asyncapi.

[github-actions]

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[AayushSaini101]

Hello guys, @fmvilas @derberg If it's fine with you, I would be glad to work on this issue under the Bounty Program, Q2-2024 as this is a potential issue for the Program.

I am already familiar with the Java templates and spring framework link](https://github.com/orgs/asyncapi/discussions/963#discussioncomment-8628690) for ease of access.
Thank you :)

[dwij2812]

Hi Team,

Wanted to check on this if we have any plans to support Pub/Sub out of the box for the most common generators, as it would be very helpful and teams need not build custom solutions and maintain them in silos?