feat(filters): add option to filter empty values for select filter

[ghiscoding]

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[codecov]

Codecov Report

Merging #310 (1a1eb1c) into master (0e89f5e) will not change coverage.
The diff coverage is 100.00%.

@@            Coverage Diff            @@
##            master      #310   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files          212       212           
  Lines        12716     12724    +8     
  Branches      4344      4350    +6     
=========================================
+ Hits         12716     12724    +8     

Impacted Files	Coverage Δ
...ackages/common/src/filters/multipleSelectFilter.ts	100.00% <100.00%> (ø)
packages/common/src/filters/selectFilter.ts	100.00% <100.00%> (ø)
packages/common/src/filters/singleSelectFilter.ts	100.00% <100.00%> (ø)
packages/common/src/services/filter.service.ts	100.00% <100.00%> (ø)
...-component/src/slick-composite-editor.component.ts	100.00% <0.00%> (ø)

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