[stable13] Fix for unbound cloned LDAP connections

[blizzz]

backport of #9325

[codecov]

Codecov Report

Merging #9522 into stable13 will decrease coverage by <.01%.
The diff coverage is 50%.

@@              Coverage Diff               @@
##             stable13    #9522      +/-   ##
==============================================
- Coverage       51.38%   51.38%   -0.01%     
- Complexity      25052    25054       +2     
==============================================
  Files            1609     1609              
  Lines           95350    95352       +2     
  Branches         1376     1376              
==============================================
+ Hits            48999    49000       +1     
- Misses          46351    46352       +1

Impacted Files	Coverage Δ	Complexity Δ
apps/user_ldap/lib/Connection.php	55.01% <50%> (-0.04%)	124 <0> (+2)
apps/files_trashbin/lib/Expiration.php	90.32% <0%> (-1.62%)	29% <0%> (ø)
apps/files_trashbin/lib/Trashbin.php	72.53% <0%> (+0.24%)	136% <0%> (ø)	⬇️