[BUG] Fix gs listing to include 0 sized marker files

[jaychia]

• Fix gs listing to include 0 sized marker files (these files are created when manually creating folders in the UI)
• Fixes also for multiple trailing delimiters
• More test coverage for recursive cases

[codecov]

Codecov Report

Merging #1412 (1bc66d5) into main (7d199d2) will decrease coverage by 0.02%.
Report is 1 commits behind head on main.
The diff coverage is n/a.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1412      +/-   ##
==========================================
- Coverage   87.79%   87.78%   -0.02%     
==========================================
  Files          60       60              
  Lines        6032     6032              
==========================================
- Hits         5296     5295       -1     
- Misses        736      737       +1     

see 1 file with indirect coverage changes