Handle unauthorized files / dirs for cleanup

[pauld-msft]

Issue reported by customer. Agents that do not even have read access to some parts of the file system can run into issues when trying to determine the files and directories that need to be cleaned up.

Fix: error handle the unauthorized exception, and skip cleanup for those cases

[codecov]

Codecov Report

Attention: Patch coverage is 81.33333% with 14 lines in your changes missing coverage. Please review.

Project coverage is 89.6%. Comparing base (91378b6) to head (0815de3).
Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
...tion.Contracts/FileComponentDetectorWithCleanup.cs	69.5%	11 Missing and 3 partials ⚠️

Additional details and impacted files

@@          Coverage Diff          @@
##            main   #1328   +/-   ##
=====================================
  Coverage   89.6%   89.6%           
=====================================
  Files        384     384           
  Lines      29930   29963   +33     
  Branches    1835    1835           
=====================================
+ Hits       26842   26875   +33     
- Misses      2696    2698    +2     
+ Partials     392     390    -2     

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[github-actions]

👋 Hi! It looks like you modified some files in the Detectors folder.
You may need to bump the detector versions if any of the following scenarios apply:

• The detector detects more or fewer components than before
• The detector generates different parent/child graph relationships than before
• The detector generates different devDependencies values than before

If none of the above scenarios apply, feel free to ignore this comment 🙂