Use Elastica's alias checking functions again

We've patched a fix into Elastica's alias checking functions to speed them
up on clusters with lots of indexes like WFM's so we can just use the built
in alias functions.

Requires Id6619ae3d2545b4a687c10af9cea8b03be89ac8c in Elastica to be fast

Bug: 61241
Change-Id: I53c808dde61e322c214673dca9f83cec34f035c7
Merge "Use Elastica's alias checking functions again"