Fixes https://github.com/owncloud/core/issues/23741

Scenario:
user0 shares a folder 'foo' with user2
user1 shares a folder 'foo' with user2
user2 logs in

Before: show only the 'foo' from user1

After: show both.

* Added intergration tests

This property can be queries by the clients so they know the max
permissions they can use to share a file with. This will improve the UX.

The oc:permissions proptery is not enough since mountpoints have
different permissions (delete + move by default).

By making it a new property the clients can just request it. On older
servers it will just return a 404 for that property (and thus they know
they have to fall back to their hacky work arounds). But if the property
is returned the client can show proper info.

* unit tests
* intergration test

Fixes #22675

Since we only get a share id we do not know the path for the sharer.
Now if we edit a share we start searching for shares for that user of
that node. And deduce the permissions that way.

* Intergration test added
* Fix unit tests

* Updated unit tests
* Added intergration test

Sharing of the users root folder should not be allowed as it is very
weird UX. Also many of our clients have no proper way of displaying
this.

Added unit test

Also added intergration tests to make sure we won't allow it in the
future.

* user with a quota of 0 gets a file shared and can't update this file
  because the wrong quota is used to verify if the update is allowed

The new sharing code handles things differently so there is no way for
create shares to handle this all properly.

* Small changes plus check of the file using propfind
* Restaured line removed accidentally

Check fields of the share response

Added missing fields to check if their values are numbers

Added tests about getting shares of a file and a test for deleting a user from a group which doesn't exist

added logic necessary for preconditions and postconditions of sharing tests

Added sharing by link tests and sharing with group

Added test which reproduces issue 19950 (adding expiration date)

refactored given and then statements to be preconditions and not operations