SF-3211 Show source panel in editor if project has source selected

[kylebuss]

This PR addresses the source panel not being displayed at times. If the project has a selected source and the user is a Paratext user we want to always display the source side panel (except on small screens where the source and target are both tabs). Cases where the source panel would automatically hide were if there was a permissions issue for the user on the source or no book found in the source. We now keep the source panel open and display a message to the user.

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This change is 

[codecov]

Codecov Report

Attention: Patch coverage is 87.87879% with 4 lines in your changes missing coverage. Please review.

Project coverage is 82.66%. Comparing base (43d2501) to head (2766889).

Files with missing lines	Patch %	Lines
...ture/ClientApp/src/app/core/permissions.service.ts	0.00%	3 Missing ⚠️
...re/ClientApp/src/app/shared/text/text.component.ts	93.75%	0 Missing and 1 partial ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #3051   +/-   ##
=======================================
  Coverage   82.66%   82.66%           
=======================================
  Files         559      559           
  Lines       32250    32268   +18     
  Branches     5240     5227   -13     
=======================================
+ Hits        26659    26675   +16     
- Misses       4809     4822   +13     
+ Partials      782      771   -11     

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