ComputerManagementDsc: Uses commands from DscResource.Common

[johlju]

Pull Request (PR) description

• ComputerManagementDsc
  • The private function Test-ResourceDscPropertyIsAssigned was removed as
    from now we should use Test-DscProperty -Name 'MyProperty' -HasValue, or
    Get-DscProperty -Name 'MyProperty' -HasValue depending what kind of
    return value is needed - Fixes Issue #407.
  • Now uses the commands Get-DscProperty and Test-DscProperty from
    the module DscResource.Common - Fixes Issue #407.
    • All uses of Get-DscProperty was changed to use the named parameter
      Attribute instead of the parameter alias Type.
    • All uses of Test-ResourceHasDscProperty was changed to use Test-DscProperty

NOTE: This PR becomes obsolete if PR #405 is merged, merging that PR will close this PR.

This Pull Request (PR) fixes the following issues

• Fixes Re-use command Get-DscProperty and Test-DscProperty from DscResource.Base #407

Task list

• Added an entry to the change log under the Unreleased section of the
  file CHANGELOG.md. Entry should say what was changed and how that
  affects users (if applicable), and reference the issue being resolved
  (if applicable).
• Resource documentation added/updated in README.md.
• Resource parameter descriptions added/updated in README.md, schema.mof
  and comment-based help.
• Comment-based help added/updated.
• Localization strings added/updated in all localization files as appropriate.
• Examples appropriately added/updated.
• Unit tests added/updated. See DSC Community Testing Guidelines.
• Integration tests added/updated (where possible). See DSC Community Testing Guidelines.
• New/changed code adheres to DSC Community Style Guidelines.

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This change is 

[codecov]

Codecov Report

Merging #408 (6c157b6) into main (41ec47e) will decrease coverage by 2%.
The diff coverage is n/a.

❗ Current head 6c157b6 differs from pull request most recent head 908e9e0. Consider uploading reports for the commit 908e9e0 to get more accurate results

@@         Coverage Diff          @@
##           main   #408    +/-   ##
====================================
- Coverage    90%    89%    -2%     
====================================
  Files        18     18            
  Lines      1802   1910   +108     
====================================
+ Hits       1629   1700    +71     
- Misses      173    210    +37     

Impacted Files	Coverage Δ
source/ComputerManagementDsc.psm1	73% <0%> (-12%)	⬇️

[johlju]

This is no longer requiered as the functions was removed as part of PR #405.