Update instructions on How to join the slack #arrow-rust channel -- or maybe try to switch to discord??

[alamb]

Discussed in #2039

^{Originally posted by HaoYang670 July 10, 2022}
Hi all.
I want to join the slack #arrow-rust channel, but it needs someone to invite me.
Could you help me?

Basically the instructions on https://github.com/apache/arrow-rs#arrow-rust-community don't really give enough information on how to join the ASF slack channel -- specifically someone already a memory needs to invite you to slack ... 🤔

I would update the instructions but I am not quite sure what it should say -- should it be file a 'question' issue? Or add a ping on the discussion thread? Or something else 🤔

[HaoYang670]

Oh, I've found the general instruction of how to join the Apache Slack channel here: https://infra.apache.org/slack.html
But for arrow-rs, there is more specific instruction (such as who to contact or where to send the request).

Personally, I prefer the @dev mailing list as a good area for sending request, which follows the Apache's style.
We can update the README to add something like that:
If you want to join the Slack channel, please send a request to dev@arrow.apache.org with title [RUST]Request joining the Slack arrow-rs channel

Also, the GitHub Discussion maybe also a good choice for sending request. But I'm not sure if this would break the Apache rule.

[alamb]

For what it is worth, @houqp made a discord channel a while ago: https://discord.com/channels/885562378132000778/885562378132000781

but mostly it serves as a place for people to ask for an invite to the ASF slack
🤷

[HaoYang670]

Not sure what happened, but I failed to join the discord channel.

[alamb]

Does this link work to join discord? https://discord.gg/YAb2TdazKQ I don't really know discord well (I think @houqp set it up originally)

[HaoYang670]

This works!