Remove return value documentation for void return types.

[wischi-chr]

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Description

Very minor code documentation fixes.

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[dlemstra]

Tnx for fixing this for us.

[JimBobSquarePants]

Needs to be fixed at the template level.

https://github.com/SixLabors/ImageSharp/blob/master/src/ImageSharp/Formats/ImageExtensions.Save.tt

[wischi-chr]

Should I change it only in the template or in both files?

[dlemstra]

Both files should be changed, I completely missed that.

[wischi-chr]

The patch now includes the fix in the template as well.

[codecov]

Codecov Report

Merging #1915 (ba73add) into master (1adb6b4) will increase coverage by 0%.
The diff coverage is n/a.

@@          Coverage Diff           @@
##           master   #1915   +/-   ##
======================================
  Coverage      87%     87%           
======================================
  Files         961     961           
  Lines       51034   51034           
  Branches     6324    6324           
======================================
+ Hits        44789   44793    +4     
+ Misses       5204    5202    -2     
+ Partials     1041    1039    -2     

Flag	Coverage Δ
unittests	87% <ø> (+<1%)	⬆️

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Impacted Files	Coverage Δ
src/ImageSharp/Formats/ImageExtensions.Save.cs	94% <ø> (ø)
...emory/DiscontiguousBuffers/MemoryGroup{T}.Owned.cs	89% <0%> (+5%)	⬆️

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