docs: decision record about API versioning

[paullatzelsperger]

What this PR changes/adds

Adds a decision record about API versioning.

Why it does that

Transparent decision traces.

Further notes

List other areas of code that have changed but are not necessarily linked to the main feature. This could be method
signature changes, package declarations, bugs that were encountered and were fixed inline, etc.

Linked Issue(s)

Closes # <-- insert Issue number if one exists

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[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Comparison is base (2dce1f0) 72.00% compared to head (acb830d) 72.00%.

❗ Current head acb830d differs from pull request most recent head 2afe0eb. Consider uploading reports for the commit 2afe0eb to get more accurate results

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Additional details and impacted files

@@           Coverage Diff           @@
##             main    #3595   +/-   ##
=======================================
  Coverage   72.00%   72.00%           
=======================================
  Files         893      893           
  Lines       17855    17855           
  Branches     1015     1015           
=======================================
  Hits        12856    12856           
  Misses       4562     4562           
  Partials      437      437           

Files	Coverage Δ
...or/api/management/asset/v3/AssetApiController.java	100.00% <ø> (ø)

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[alexandrudanciu]

Proposed some minor improvements.