[BUGFIX] Relations to the same table in Extbase

This patch introduces a mapping for properties to table aliases in
the Extbase Typo3DbQueryParser. This allows relations between
identical classes / tables.

Releases: master, 6.2
Resolves: #27057
Change-Id: If1e88c994b8a1179f6babf2bdfc1da3e61b2c658