Speedup slow tests due to rate limit

[KENNYSOFT]

Speedup slow tests due to rate limit.
Total execution time is reduced from 10 minutes to 4 minutes, which is 2.5x faster or saving 6 minutes each.

Reference: https://github.com/KENNYSOFT/java-slack-sdk/actions/runs/10939043557/job/30368464798

Category (place an x in each of the [ ])

• bolt (Bolt for Java)
• bolt-{sub modules} (Bolt for Java - optional modules)
• slack-api-client (Slack API Clients)
• slack-api-model (Slack API Data Models)
• slack-api-*-kotlin-extension (Kotlin Extensions for Slack API Clients)
• slack-app-backend (The primitive layer of Bolt for Java)

Requirements

Please read the Contributing guidelines and Code of Conduct before creating this issue or pull request. By submitting, you agree to those rules.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 74.28%. Comparing base (d5e0036) to head (9cd4793).
Report is 1 commits behind head on main.

Additional details and impacted files

@@             Coverage Diff              @@
##               main    #1377      +/-   ##
============================================
- Coverage     74.39%   74.28%   -0.12%     
+ Complexity     4276     4270       -6     
============================================
  Files           461      461              
  Lines         13347    13347              
  Branches       1370     1370              
============================================
- Hits           9930     9915      -15     
- Misses         2617     2625       +8     
- Partials        800      807       +7     

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

[seratch]

Great, thank you so much!