Prevent item labels in Collection modal from being cut off

[regisrob]

Fixes #3424

Example Manifest: https://portail.biblissima.fr/iiif/collection/ark:/43093/coldata5151005ea5833e5a05e2639cbb210946cb7e0609

[codecov-commenter]

Codecov Report

Merging #3432 (e707c1b) into master (f04f89f) will decrease coverage by 0.05%.
The diff coverage is 25.00%.

❗ Current head e707c1b differs from pull request most recent head fab63ef. Consider uploading reports for the commit fab63ef to get more accurate results

@@            Coverage Diff             @@
##           master    #3432      +/-   ##
==========================================
- Coverage   88.99%   88.94%   -0.06%     
==========================================
  Files         196      196              
  Lines        3398     3400       +2     
==========================================
  Hits         3024     3024              
- Misses        374      376       +2     

Impacted Files	Coverage Δ
src/components/CollectionDialog.js	54.16% <25.00%> (-2.36%)	⬇️

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[cbeer]

I've added a screenshot above. @ggeisler, does this look ok?

[ggeisler]

@regisrob @cbeer Yes, this looks great to me.

That screenshot illustrates another minor styling issue: the main content area (from the Resource heading down) needs to be indented an additional 10px or so so that it is left-aligned with the header content. But that is a different issue so I can create a separate ticket for that if we want to keep this one simple and get it merged.