[TASK] Deferred reference index updating

Within DataHandler processing, updating the reference index
is an expensive task since it needs tons of queries to do
the job.

With DataHandler instances and it's sub instances created
for relations and localizations, the code tends to update the
reference index for the same table/uid combination multiple times:
As example, core test IRRE/ForeignField/Modify copyParentContent()
copies a content element with one hotel, one offer and one price
around. This leads to 3 update reference index calls for the
tt_content element, 4 for the hotel, 4 for the offer and 3 for
the price.
Of course, the situation is worse in workspaces.

There have been various attempts over the years to reduce the
query load, usually by adding runtime caches everywhere.

With proper sys_refindex functional test coverage in place, we
can however finally solve the root problem: The patch adds the
helper object ReferenceIndexUpdater to fill a registry with
to-update workspace/table/uid combinations. The object is carried
around within DataHandler and RelationHandler to DataHandler sub
instances. Only the outer most instance of a DataHandler then
finally executes the update() operations in one go and only
once per combination.

The patch tries to be rather conservative to allow a 10.4 backport.
For master, there should be further mess-reducing cleanup patches
to streamline related parts of the ReferenceIndex update process.

Result: The DataHandler query load is reduced significantly. It
heavily depends on the structure that is changed, to get an idea,
the above test goes down from 448 queries to 346 queries!

Change-Id: I49f5ed73114ca5d6e2cb75fa43846bde5ea72d26
Resolves: #92356
Related: #88134
Releases: master, 10.4
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/65796


Tested-by: Oliver Bartsch <bo@cedev.de>
Tested-by: TYPO3com <noreply@typo3.com>
Tested-by: Benni Mack <benni@typo3.org>
Tested-by: Georg Ringer <georg.ringer@gmail.com>
Reviewed-by: Oliver Bartsch <bo@cedev.de>
Reviewed-by: Benni Mack <benni@typo3.org>
Reviewed-by: Georg Ringer <georg.ringer@gmail.com>