Avoid to truncate WHERE clauses when clonning the querybuilder

[antograssiot]

Q	A
Bug fix?	yes
New feature?	yes/no
BC breaks?	no
Deprecations?	no
Tests pass?	yes
Fixed tickets
License	MIT
Doc PR

This PR aims to fix a bug introduced by #950
Actually when the querybuilder is cloned, some where parts are stripped.

The issue comes from

    // Change where aliases
    foreach ($wherePart->getParts() as $where) {
        $queryBuilderClone->add('where', str_replace($aliases, $replacements, $where));
    }

because the add() function doesn't append.

There's probably a cleaner way of fixing this, please let me know and i'll update

[antograssiot]

Closing in favor of #1010