chore: group docusaurus dependencies

[WilliamBergamin]

Summary

#1547 Failed with the following error message found in the CI pipeline

[cause]: Error: Invalid name=docusaurus-plugin-content-docs version number=3.5.2.
  All official @docusaurus/* packages should have the exact same version as @docusaurus/core (number=3.4.0).
  Maybe you want to check, or regenerate your yarn.lock or package-lock.json file?

This PR attempts to configure dependabot grouping for docusaurus dependencies. This should allow dependabot to update all docusaurus dependencies in one since PR preventing this type of breakage 🤔

Category

• slack_sdk.web.WebClient (sync/async) (Web API client)
• slack_sdk.webhook.WebhookClient (sync/async) (Incoming Webhook, response_url sender)
• slack_sdk.socket_mode (Socket Mode client)
• slack_sdk.signature (Request Signature Verifier)
• slack_sdk.oauth (OAuth Flow Utilities)
• slack_sdk.models (UI component builders)
• slack_sdk.scim (SCIM API client)
• slack_sdk.audit_logs (Audit Logs API client)
• slack_sdk.rtm_v2 (RTM client)
• /docs (Documents)
• /tutorial (PythOnBoardingBot tutorial)
• tests/integration_tests (Automated tests for this library)

Requirements

• I've read and understood the Contributing Guidelines and have done my best effort to follow them.
• I've read and agree to the Code of Conduct.
• I've run python3 -m venv .venv && source .venv/bin/activate && ./scripts/run_validation.sh after making the changes.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 84.96%. Comparing base (701daac) to head (1c6245d).
Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1553      +/-   ##
==========================================
+ Coverage   84.94%   84.96%   +0.02%     
==========================================
  Files         113      113              
  Lines       12501    12501              
==========================================
+ Hits        10619    10622       +3     
+ Misses       1882     1879       -3     

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.