Warn about complete separation issues

[strengejacke]

No description provided.

[codecov]

Codecov Report

Merging #913 (5802890) into main (cec62fa) will increase coverage by 0.01%.
The diff coverage is 78.57%.

❗ Current head 5802890 differs from pull request most recent head 1958e3e. Consider uploading reports for the commit 1958e3e to get more accurate results

@@            Coverage Diff             @@
##             main     #913      +/-   ##
==========================================
+ Coverage   57.91%   57.92%   +0.01%     
==========================================
  Files         186      186              
  Lines       13925    13938      +13     
==========================================
+ Hits         8064     8074      +10     
- Misses       5861     5864       +3     

Files	Coverage Δ
R/ci_profile_boot.R	70.83% <100.00%> (+0.62%)	⬆️
R/format.R	72.45% <72.72%> (+<0.01%)	⬆️