feat: Slack bot

[cachho]

Description

Tested, works.

I removed from slackeventsapi import SlackEventAdapter because

a) I couldn't get the event to fire
b) it's essentially just a flask wrapper and we're using flask anyways.
c) it provides little abstraction, it just gives you the json

So yes, I implemented that myself.

Other things to note:

• event subscribtion verification (requests url) works out of the box with this, you just have to run it.
• this makes getting the SLACK_SIGNING_TOKEN absolete.
• the add method of this bot still uses the data_type
• data_types that don't use a string won't work. As far as I know that's only qna_pair at the moment
• documentation hasn't been updated. I don't know if you want to keep stuff that references the examples folder. I also don't know if you want this to still be hosted on replit.

Fixes #

Type of change

Please delete options that are not relevant.

• New feature (non-breaking change which adds functionality)

How Has This Been Tested?

Please describe the tests that you ran to verify your changes. Provide instructions so we can reproduce. Please also list any relevant details for your test configuration

Please delete options that are not relevant.

• Unit Test
• Test Script (please provide)
• End-to-end-test in slack

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• Any dependent changes have been merged and published in downstream modules
• I have checked my code and corrected any misspellings

Maintainer Checklist

• closes #xxxx (Replace xxxx with the GitHub issue number)
• Made sure Checks passed

[deshraj]

Looks good in general. Left some minor comments.

[taranjeet]

Hey @cachho : the PR looks good. can you please add some docs?

[cachho]

Hey @cachho : the PR looks good. can you please add some docs?

ok, will remove examples folder example. Will try to keep replit.

[cachho]

Made the changes. Didn't see a reason to keep replit, as this can be self-hosted with ngrok, just like the other examples.