EDGE-614 update renovate.json to use the renovate-config-public repo

[Yaseen-A-Khan]

This PR updates the renovate.json which now should point to the repo renovate-config-public which defines the renovate settings.

[gemini-code-assist]

Code Review

This pull request updates the Renovate configuration in .github/renovate.json by extending the local public configuration from Cognite Data and enabling digest pinning. There are no review comments, and I have no feedback to provide.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 82.73%. Comparing base (600b62b) to head (ed6be40).
⚠️ Report is 1 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #545      +/-   ##
==========================================
+ Coverage   82.68%   82.73%   +0.04%     
==========================================
  Files          44       44              
  Lines        4430     4430              
==========================================
+ Hits         3663     3665       +2     
+ Misses        767      765       -2     

see 1 file with indirect coverage changes

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[thorkildcognite]

🦄 LGTM -- this public repo will not have any dependencies to internal repositores, so makes sense to use the -public variant.