Select: Required now also works when MultiSelection="true" (#4328, #4346)

[gismofx]

Description

Fixes #4328
MudSelect When Required=true and MultiSelection=true Required Value check now works. Fixed by overriding HasValue method in MudSelect.

How Has This Been Tested?

Test Added To SelectTests
MultiSelectWithRequiredValue

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)

Checklist:

• The PR is submitted to the correct branch (dev).
• My code follows the code style of this project.
• I've added relevant tests.

[gismofx]

I ran all tests locally:

[codecov]

Codecov Report

Merging #4346 (17e330e) into dev (4d9a839) will decrease coverage by 0.04%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##              dev    #4346      +/-   ##
==========================================
- Coverage   91.22%   91.17%   -0.05%     
==========================================
  Files         361      361              
  Lines       12450    12461      +11     
==========================================
+ Hits        11357    11361       +4     
- Misses       1093     1100       +7     

Impacted Files	Coverage Δ
src/MudBlazor/Components/Select/MudSelect.razor.cs	96.72% <100.00%> (+0.02%)	⬆️
...r/Components/Autocomplete/MudAutocomplete.razor.cs	91.16% <0.00%> (-2.99%)	⬇️
...c/MudBlazor/Components/Popover/MudPopover.razor.cs	84.21% <0.00%> (-0.79%)	⬇️

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[gismofx]

Please wait on merge. I have fixed a typo in the test and need add two more checks to the test to show that the required error is not present when MultiSelect has value(s). Standby by please

[gismofx]

Ready for review :)

[mckaragoz]

Looking good for me

[henon]

Perfect! Thanks