add slack to github integrations list

[ParkourKarthik]

Why:

closes#432

What's being changed:

Included slack to github integration list

Check off the following:

• All of the tests are passing.
• I have reviewed my changes in staging.
• For content changes, I have reviewed the localization checklist
• For content changes, I have reviewed the Content style guide for GitHub Docs.

[welcome]

Thanks for opening this pull request! A GitHub docs team member should be by to give feedback soon. In the meantime, please check out the contributing guidelines.

[janiceilene]

Thanks so much for opening a PR @ParkourKarthik! I'll get this triaged for review 🎉

[felicitymay]

Hi. Thanks for picking this issue up. It'll be really helpful for users to have a fuller list of integrations created by GitHub. ✨

I've made a couple of suggestions of small changes to improve clarity.

It's not suggested in the issue but, if you have time, it would be great to add links from the Jira and Slack sections to the marketplace docs - using the same format as for the Editor tools. The information there is quite detailed:

• Jira information: https://github.com/marketplace/jira-software-github
• Slack information: https://github.com/marketplace/slack-github

[felicitymay]

Thanks for the changes. Can you let me know if you plan to add the links I suggested too? I don't want to merge the PR if you're planning further work.

[ParkourKarthik]

@felicitymay Sure, will work on updating the links as preferred.

[felicitymay]

Sure, will work on updating the links as preferred.

Thanks, that sounds good. 🙇🏻‍♀️
I think this is really worth doing as it will mean that we don't have to update the notes you've added if new functionality is added to the integrations, but people can easily follow up to see the latest information. I'll keep an eye open for further changes to this pull request.

[felicitymay]

Thanks for adding the links. This topic looks much better with your work 💎 ✨

I'll update your branch from main and merge.

[github-actions]

Thanks very much for contributing! Your pull request has been merged 🎉 You should see your changes appear on the site in approximately 24 hours.

[felicitymay]

🎉 🚢

I think that you might need to close the issue that you've fixed manually, since this PR wasn't mentioned as a fix for #432. I should have noticed that before and then I could have added a comment to link the PR to the issue before I merged 🤦🏻

(For reference: https://docs.github.com/en/free-pro-team@latest/github/managing-your-work-on-github/linking-a-pull-request-to-an-issue.)

[ParkourKarthik]

Sorry that I missed. I can't close the issue as I don't have the option ( probably rights). Tried updating the description here but didn't work 🤷

[felicitymay]

Ah. No problem - I didn't realize. I'll update the issue shortly (in a meeting right now).