feat(swarm): Add wasm-bindgen executor

[umgefahren]

Description

Add a wasm-bindgen executor to perform concurrent connections on browser or node background tasks.

Links to any relevant issues

Result of: #3097 (comment)

Open Questions

None

Change checklist

• I have performed a self-review of my own code
• I have made corresponding changes to the documentation
• I have added tests that prove my fix is effective or that my feature works
• A changelog entry has been made in the appropriate crates

Commit message body

[mxinden]

Thanks @umgefahren for the work here!

From my minimal WASM knowledge, this looks good to me.

@vincev curious what your thoughts are here given your example #2617 (comment).

[vincev]

Thanks @umgefahren for the work here!

From my minimal WASM knowledge, this looks good to me.

@vincev curious what your thoughts are here given your example #2617 (comment).

@mxinden looks nice it makes it easier to create the Swarm I will update the example to use with_wasm_executor.

[thomaseizinger]

Rustfmt is not happy, otherwise this LGTM!

[mergify]

This pull request has merge conflicts. Could you please resolve them @umgefahren? 🙏

[mxinden]

After merging #3083 which touched the mergify configuration, Mergify is complaining that "The current Mergify configuration is invalid", see also https://github.com/libp2p/rust-libp2p/pull/3115/checks?check_run_id=9673900404.

warning The subscription needs to be updated to enable this feature.

Unfortunately I don't have access to the libp2p Mergify subscription page, thus I am not sure what it entails to "update the subscribtion".

@galargh do you have access? Can you check what we would need to do to "update the subscription"?

//CC @thomaseizinger

[thomaseizinger]

Oh my god :(

https://docs.mergify.com/actions/post_check/#enforcing-conventional-commits

post_check's are a premium feature! I completely overlooked that! Sorry about that.

I suggest we revert #3083 for now.

[thomaseizinger]

Unfortunately I don't have access to the libp2p Mergify subscription page

You do have access to the dashboard though, right?

[mxinden]

Unfortunately I don't have access to the libp2p Mergify subscription page

You do have access to the dashboard though, right?

I do. Is there some way that is helpful?

[mxinden]

I suggest we revert #3083 for now.

👍 done via #3165.

[thomaseizinger]

Unfortunately I don't have access to the libp2p Mergify subscription page

You do have access to the dashboard though, right?

I do. Is there some way that is helpful?

Only to inspect the current merge queue. I just wanted to make sure this isn't tied to my account only for some reason.