enable caldav for webdav subtree public-calendars

[georgehrke]

fixes public calendar sharing

[codecov]

Codecov Report

Merging #9798 into master will decrease coverage by <.01%.
The diff coverage is 100%.

@@             Coverage Diff              @@
##             master    #9798      +/-   ##
============================================
- Coverage     51.92%   51.92%   -0.01%     
  Complexity    25768    25768              
============================================
  Files          1635     1635              
  Lines         95426    95426              
  Branches       1308     1308              
============================================
- Hits          49553    49552       -1     
- Misses        45873    45874       +1

Impacted Files	Coverage Δ	Complexity Δ
apps/dav/lib/Server.php	47.79% <100%> (ø)	22 <0> (ø)	⬇️
apps/files_trashbin/lib/Trashbin.php	72.46% <0%> (-0.25%)	136% <0%> (ø)

[georgehrke]

@rullzer Is the subtree thing tested anywhere? Can't find something relevant in the ServerTest.php

[rullzer]

@georgehrke not explicitly I think