Support DictionaryArray in add_scalar kernel

[viirya]

Which issue does this PR close?

Closes #2017.

Rationale for this change

What changes are included in this PR?

Are there any user-facing changes?

[viirya]

cc @sunchao

[sunchao]

LGTM

[codecov-commenter]

Codecov Report

Merging #2018 (a4e99e8) into master (62053a8) will increase coverage by 0.01%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master    #2018      +/-   ##
==========================================
+ Coverage   83.58%   83.59%   +0.01%     
==========================================
  Files         222      222              
  Lines       57639    57669      +30     
==========================================
+ Hits        48180    48211      +31     
+ Misses       9459     9458       -1     

Impacted Files	Coverage Δ
arrow/src/compute/kernels/arithmetic.rs	92.35% <100.00%> (+0.40%)	⬆️
parquet_derive/src/parquet_field.rs	66.21% <0.00%> (+0.22%)	⬆️

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[viirya]

Thanks @sunchao