Added Public Function Find-Certificate

[hollanjs]

Pull Request (PR) description

Moved Find-Certificate from a utility function in CertificateDsc.Common.psm1 to a public function in DscResource.Common. Related to CertificateDsc Issue #272

This Pull Request (PR) fixes the following issues

• Fixes #100

Task list

• [x] 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).
• [x] Documentation added/updated in README.md.
• [x] Comment-based help added/updated for all new/changed functions.
• [x] Localization strings added/updated in all localization files as appropriate.
• [x] Examples appropriately added/updated.
• [x] Unit tests added/updated. See DSC Community Testing Guidelines.
• [ ] Integration tests added/updated (where possible). See DSC Community Testing Guidelines.
• [x] New/changed code adheres to DSC Community Style Guidelines.

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This change is 

[codecov[bot]]

Codecov Report

Merging #101 (ed4d7d9) into main (c5ef7be) will increase coverage by 0%. The diff coverage is 100%.

:exclamation: Current head ed4d7d9 differs from pull request most recent head 3a0111b. Consider uploading reports for the commit 3a0111b to get more accurate results

@@         Coverage Diff         @@
##           main   #101   +/-   ##
===================================
  Coverage    91%    92%           
===================================
  Files        34     35    +1     
  Lines       599    628   +29     
===================================
+ Hits        550    579   +29     
  Misses       49     49           

Impacted Files	Coverage Δ
source/Public/Find-Certificate.ps1	100% <100%> (ø)

[johlju]

I forgot about this. I have been working a lot lately so I haven't been able do much community work. Will try to look at this soon.

[johlju]

@hollanjs sorry for tasking so long wit this one. Just a tiny comment.