[BUGFIX] Ensure rootline order is respected detecting closest template

[calien666]

What this pr does

When detecting the closest template inside a rootline, it is necessary, respecting the order of the rootline itself.

The current database call has a random sorting, which does not respect the ordering, therefore, could return a wrong dataset if multiple templates are given in the root line.

To ensure the order is respected, every page inside rootline is called single against the database and returns the pid if a template record exists.

How to test

Given a rootline with multiple siteroots, the database query does not respect the order of the elements and only returns the first hit form the database, which could be the right looked up, but not has to be.

Example build:

0
|- 165 (doktype 254)
 |- 271 (doktype 1, is siteroot, has root template)
  |- 348 (doktype 254)
   |- 396 (doktype 254)
    |- 491 (doktype 1, is siteroot, has root template)
     |- 29455 (doktype 254)
      |- 29456 (doktype 254, Records located here)

The system calls with the rootline:

7 => 29456
6 => 29455
5 => 491
4 => 396
3 => 348
2 => 271
1 => 165

And the database always returns 271 as the found pid, which is wrong.

Fixes: #4012

[calien666]

Additional information: I detected this issue already int EXT:solr 11, as we are working on a TYPO3 v11, but the logic is the same for later versions.