Update NiceGuy.io links in integrations-community.md

[Abrifq]

📑 Summary

I got notified from my fork that the niceguy's links were not working, looks like they updated their sitemap and this PR updates the relevant parts!

Resolves: link checker fails about niceguy dot io

📏 Design Decisions

Updated the links.

📋 Tasks

Make sure you

• 📖 have read the contribution guidelines
• ❌ 💻 have added necessary unit/e2e tests.
• ❌ 📓 have added documentation. Make sure MERMAID_RELEASE_VERSION is used for all new features.
• 🔖 targeted develop branch

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[codecov]

Codecov Report

Merging #5120 (1d08155) into develop (cc4af0c) will increase coverage by 0.02%.
The diff coverage is n/a.

❗ Current head 1d08155 differs from pull request most recent head f476c25. Consider uploading reports for the commit f476c25 to get more accurate results

Additional details and impacted files

@@             Coverage Diff             @@
##           develop    #5120      +/-   ##
===========================================
+ Coverage    79.37%   79.40%   +0.02%     
===========================================
  Files          166      166              
  Lines        13877    13877              
  Branches       705      705              
===========================================
+ Hits         11015    11019       +4     
+ Misses        2710     2706       -4     
  Partials       152      152              

Flag	Coverage Δ
e2e	85.22% <ø> (+0.03%)	⬆️
unit	43.04% <ø> (ø)

Flags with carried forward coverage won't be shown. Click here to find out more.

see 3 files with indirect coverage changes

[Abrifq]

Thanks for merging! Can someone on team check mermaid-js/mermaid-live-editor#1335 as well?

Having the docs in the editor is important (as always) and I don't want this PR to go stale.

Have a nice week!