Remove the loop of calendars when only one is needed

[miaulalala]

Fixes#33599

[tcitworld]

Good enough for now, but I suggest the following to make psalm happy properly (possibly as an extra PR):

• Add a new interface DirectURIAccess providing the getCalendarByUri and getSubscriptionByUri.
• Implement getSubscriptionByUri in CalDAV backend
• This allows to do pretty much the same for subscriptions below (more speed ⚡ )
• Put all of this into a if ($this->caldavBackend instanceof DirectURIAccess) check so that psalm is happy and we're keeping things clean).

[tcitworld]

Testing trashbin should work the same btw, through a TrashbinSupport interface.

[CarlSchwan]

Still some failures in drone

[miaulalala]

Drone failures with file sharing acceptance tests (unrelated?)

[nickvergessen]

Maybe a rebase can tell?

[st3iny]

Rebased to (hopefully) fix tests.

[ChristophWurst]

Drone restarted

[blizzz]

Linter is unhappy

[miaulalala]

Drone failure due to:

latest: Pulling from nextcloud/continuous-integration-php8.0
--
2 | Digest: sha256:3708f22218d6e3b8477d653fd83bf75230b8b61f0be9c25c162d96a14e89661f
3 | Status: Image is up to date for ghcr.io/nextcloud/continuous-integration-php8.0:latest
4 | + bash tests/drone-run-php-tests.sh \|\| exit 0
5 | =========================
6 | = List of changed files =
7 | =========================
8 | apps/dav/lib/CalDAV/CalendarHome.php
9 | apps/dav/tests/unit/CalDAV/CalendarHomeTest.php
10 | =========================
11 | PHP files are modified
12 | + NOCOVERAGE=true TEST_SELECTION=DB ./autotest.sh mariadb
13 | Using PHP executable /usr/bin/php
14 | Using database oc_autotest
15 | Setup environment for mariadb testing on local storage ...
16 | Waiting for MariaDB initialisation ...
17 | ............................................................................................................................................................................................................................................................................................................
18 | [ERROR] Waited 300 seconds, no response