WIP: Safer cell sizing option

[Djspaceg]

Checklist

• I have read and understand the contribution guide

• A CHANGELOG entry is included

• At least one test case is included for this feature or bug fix

• Documentation was added or is not needed

• This is an API breaking change

Issue Resolved / Feature Added

Cell doesn't allow for an option that shrinks to the size of the content, but stops at the boundary for the Layout.

Resolution

Cell now supports a size="content" option which does exactly that. The layout is allowed to flex in height while the cell fits the available space without going over.

[codecov]

Codecov Report

Merging #2795 into develop will decrease coverage by 0.00%.
The diff coverage is 87.50%.

@@             Coverage Diff             @@
##           develop    #2795      +/-   ##
===========================================
- Coverage    44.62%   44.62%   -0.01%     
===========================================
  Files          163      163              
  Lines         8199     8200       +1     
  Branches      2000     2001       +1     
===========================================
  Hits          3659     3659              
- Misses        3408     3409       +1     
  Partials      1132     1132              

Impacted Files	Coverage Δ
packages/ui/Layout/Layout.js	94.44% <ø> (ø)
packages/ui/Layout/Cell.js	94.44% <87.50%> (-5.56%)	⬇️

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