Fix initializing paged search under some circumstances

[blizzz]

Fixes#5273 and #6388

Basically the issue was, that a paged search might not be properly initialized, when no limit was given, but a previous search had a limit set. This resulted in strange behaviour as described in #5273. While debugging this, I figured out, @eigood recently also saw the wrong spot in the code as described in #6388.

Added Paged Search Integration tests cover the case.

Please test and review @nextcloud/ldap @zfzfzf33@eigood@bline

Backport is necessary.

[MorrisJobke]

Existing and new LDAP config works 👍

[rullzer]

Seems to still work on my ldap test instance :)

[MorrisJobke]

Let me rebase to get the latest fixes on master.

[MorrisJobke]

Rebased

[codecov]

Codecov Report

Merging #6453 into master will decrease coverage by 2.13%.
The diff coverage is 0%.

@@ Coverage Diff @@## master #6453 +/- ##
===========================================
- Coverage 55.53% 53.4% -2.14% - Complexity 21243 22521 +1278 
===========================================
Files 1253 1407 +154 Lines 73203 87100 +13897 Branches 0 1329 +1329 ===========================================
+ Hits 40653 46513 +5860 - Misses 32550 40587 +8037

Impacted Files	Coverage Δ	Complexity Δ
apps/user_ldap/lib/Group_LDAP.php	60.11% <0%> (ø)	160 <0> (ø)	⬇️
apps/user_ldap/lib/Access.php	18.2% <0%> (-0.1%)	304 <0> (+3)
apps/sharebymail/tests/SettingsTest.php	52.17% <0%> (-47.83%)	3% <0%> (ø)
lib/private/Security/RateLimiting/Limiter.php	55.55% <0%> (-44.45%)	5% <0%> (ø)
settings/Controller/EncryptionController.php	56% <0%> (-37.34%)	8% <0%> (ø)
settings/Controller/GroupsController.php	64.61% <0%> (-35.39%)	9% <0%> (ø)
...ps/comments/tests/Unit/AppInfo/ApplicationTest.php	69.56% <0%> (-30.44%)	4% <0%> (ø)
apps/user_ldap/lib/Configuration.php	41.5% <0%> (-29.46%)	86% <0%> (ø)
apps/encryption/lib/Command/EnableMasterKey.php	75% <0%> (-25%)	5% <0%> (ø)
lib/private/AvatarManager.php	61.9% <0%> (-24.77%)	4% <0%> (ø)
... and 344 more

[blizzz]

backports for 12: #6502 and 11: #6504

[MorrisJobke]

Waiting for CI: https://drone.nextcloud.com/nextcloud/server/1537

[blizzz]

Waiting for CI: https://drone.nextcloud.com/nextcloud/server/1537

error during connect: Post http://%2Fvar%2Frun%2Fdocker.sock/v1.26/networks/create: EOF

😭

[MorrisJobke]

@blizzz Ignore that single occurrence for now