Remove DBAL dependency

aaron.ferris → made their first commit to this issue’s fork.

Looks safe to remove, its not listed in the 5.x .info file, can't find any references to dbal in the code base outside of this:

entity_hierarchy.views.inc

// @see \PNX\NestedSet\Storage\DbalNestedSetSchema::create() which isn't immediately obvious to my eyes how the following code relates....