DSC_Computer: Fix for Delete-ADSIObject

[rcarpenter79]

Pull Request (PR) description

This fixes the function Delete-ADSIObject by changing the variable used when creating System.DirectoryServices.DirectoryEntry.

This Pull Request (PR) fixes the following issues

Fixes #414

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 #415 (4fb3695) into main (fcff2e0) will decrease coverage by 1%.
The diff coverage is 100%.

@@         Coverage Diff         @@
##           main   #415   +/-   ##
===================================
- Coverage    90%    90%   -1%     
===================================
  Files        18     18           
  Lines      1802   1801    -1     
===================================
- Hits       1629   1628    -1     
  Misses      173    173           

Impacted Files	Coverage Δ
source/DSCResources/DSC_Computer/DSC_Computer.psm1	90% <100%> (-1%)	⬇️

[johlju]

Reviewed 2 of 2 files at r1, all commit messages.
Reviewable status: complete! all files reviewed, all discussions resolved (waiting on @rcarpenter79)