[glean] Remove reflexive LocalDeclarationReference facts from flow indexer
[glean] Remove reflexive LocalDeclarationReference facts from flow indexer

Summary: `LocalDeclarationReference` facts are meant to associate uses of a variable with its declaration. The declaration is not a use, so it was not correct for these facts to be reflexive, and it was causing confusion. This diff fixes that.

Reviewed By: donsbot

Differential Revision: D28480032

fbshipit-source-id: 003c7dcdd609db87db358124c31acfd2abbbfc03

facebook/flow,mroch/flow,mroch/flow,mroch/flow,facebook/flow,facebook/flow,facebook/flow,facebook/flow,mroch/flow,mroch/flow,mroch/flow,facebook/flow,facebook/flow,mroch/flow