Implementing the list-payments endpoint's join argument

[jopmiddelkamp]

Is your feature request related to a problem? Please describe.
We currently cannot join our transactions into our transaction operations.

This is because the optional join argument is not implemented yet.
https://developers.stellar.org/api/resources/operations/list-payments/

Describe the solution you'd like
An implementation of the join argument on the list-payments endpoint. For example: https://horizon.stellar.org/payments?join=transactions

Describe alternatives you've considered
Using the transactions endpoint and manually filtering out all payment operations. But this is something we really would not like to do..

Additional context
Nope.

[elucidsoft]

@jopmiddelkamp Do you think you could fix this and submit a PR for review?

[jopmiddelkamp]

I already tried before creating the request but I can't get the project to work on my MacBook.. the .NET version being used is too old. The installers don't work on newer Mac os versions due to security improvements.

It would be nice if one of the maintainers could do it otherwise I'd have to somehow arrange/purchase all kinds of things to run Windows. Not that that is impossible but would not be my preference. This way it'll take me a lot of time to do a small change. While for you guys it's probably fixed quickly if I'm not wrong.

[elucidsoft]

@jopmiddelkamp No problem, I am upgrading the .NET version in next major release to .NET 6.x btw.

[GuyWhoKnowsTheGuy]

@jopmiddelkamp The master branch is now on .NET 6. Please let us know if you're still interested in creating a PR. Thanks!