DM-32144: Suppress warnings for cartesian join

[andy-slac]

Some queries involving user expression can generate cartesian join,
it is harmless as it should normally be constrained to a single row in
a joined table. Instead of trying to avoid cartesian joins we simply
suppress sqlalchemy warnings for one type of query.

Checklist

• ran Jenkins
• added a release note for user-visible changes to doc/changes

[codecov]

Codecov Report

Merging #608 (1f7e14e) into main (19c4ce5) will increase coverage by 0.00%.
The diff coverage is 100.00%.

❗ Current head 1f7e14e differs from pull request most recent head 7363b56. Consider uploading reports for the commit 7363b56 to get more accurate results

@@           Coverage Diff           @@
##             main     #608   +/-   ##
=======================================
  Coverage   83.67%   83.67%           
=======================================
  Files         242      242           
  Lines       30703    30706    +3     
  Branches     4595     4595           
=======================================
+ Hits        25691    25694    +3     
  Misses       3814     3814           
  Partials     1198     1198           

Impacted Files	Coverage Δ
...ython/lsst/daf/butler/registry/dimensions/table.py	84.41% <100.00%> (+0.20%)	⬆️

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