xml2lang retains some whitespace

[MichaelChirico]

Closes #2131

The key for a reprex is that removing whitespace causes a parse failure, so if (A) x else y won't work because if (A) xelsey is actually fine, and apparently if (A) "" else "" is also fine. if (A) "" else y is the shortest I could see that causes the parse failure when is stripped.

[codecov-commenter]

Codecov Report

Merging #2132 (ce59503) into main (9bd015d) will increase coverage by 0.00%.
Report is 1 commits behind head on main.
The diff coverage is 100.00%.

❗ Current head ce59503 differs from pull request most recent head 2438526. Consider uploading reports for the commit 2438526 to get more accurate results

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##             main    #2132   +/-   ##
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  Coverage   99.64%   99.64%           
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  Files         112      112           
  Lines        5116     5125    +9     
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+ Hits         5098     5107    +9     
  Misses         18       18           

Files Changed	Coverage Δ
R/lint.R	98.88% <100.00%> (+0.02%)	⬆️
R/utils.R	99.05% <100.00%> (ø)