Do not create the default folders for DirectoryStore on Open

[mregen]

Proposed changes

For convenience, the DirectoryStore class creates the default folders when the DirectoryStore is opened. (since #2720) However this may lead into issues mapping folders to the store when started in docker.

Fix: remove the code which creates default folders and ensure a null directory does not throw a NullReferenceException.

Related Issues

• Fixes #2720

Types of changes

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• [x] Bugfix (non-breaking change which fixes an issue)
• [ ] Enhancement (non-breaking change which adds functionality)
• [ ] Test enhancement (non-breaking change to increase test coverage)
• [ ] Breaking change (fix or feature that would cause existing functionality to not work as expected, requires version increase of Nuget packages)
• [ ] Documentation Update (if none of the other choices apply)

Checklist

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Further comments

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[codecov[bot]]

Codecov Report

Attention: Patch coverage is 33.33333% with 2 lines in your changes missing coverage. Please review.

Project coverage is 54.72%. Comparing base (5349d9a) to head (8da3156). Report is 4 commits behind head on master.

Files with missing lines	Patch %	Lines
...Security/Certificates/DirectoryCertificateStore.cs	33.33%	0 Missing and 2 partials :warning:

Additional details and impacted files

```diff @@ Coverage Diff @@ ## master #2773 +/- ## ========================================== + Coverage 54.62% 54.72% +0.09% ========================================== Files 349 349 Lines 65705 65691 -14 Branches 13446 13442 -4 ========================================== + Hits 35889 35947 +58 + Misses 25923 25861 -62 + Partials 3893 3883 -10 ```

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[mregen]

@ThomasNehring I removed the other create and added some more sanity check for null, just to be safe