Fixed extend when additional is zero

[jorgecarleitao]

Also added an extra test for it.

[codecov]

Codecov Report

Merging #310 (9423aed) into main (bbe607c) will increase coverage by 0.27%.
The diff coverage is 95.65%.

@@            Coverage Diff             @@
##             main     #310      +/-   ##
==========================================
+ Coverage   80.52%   80.79%   +0.27%     
==========================================
  Files         323      324       +1     
  Lines       21135    21569     +434     
==========================================
+ Hits        17019    17427     +408     
- Misses       4116     4142      +26     

Impacted Files	Coverage Δ
src/bitmap/mutable.rs	89.27% <50.00%> (-0.34%)	⬇️
tests/it/bitmap/mutable.rs	100.00% <100.00%> (ø)
src/compute/comparison/primitive.rs	95.12% <0.00%> (-0.20%)	⬇️
tests/it/io/json/mod.rs	100.00% <0.00%> (ø)
tests/it/array/fixed_size_binary/mutable.rs	100.00% <0.00%> (ø)
src/compute/comparison/simd/mod.rs	95.83% <0.00%> (ø)
src/array/primitive/mutable.rs	88.44% <0.00%> (+1.34%)	⬆️
src/io/json/read/reader.rs	75.67% <0.00%> (+1.35%)	⬆️
src/compute/comparison/mod.rs	95.62% <0.00%> (+2.00%)	⬆️
src/array/fixed_size_binary/mod.rs	50.84% <0.00%> (+3.57%)	⬆️
... and 4 more

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