Revert "Bug 570907 - A processingStep to verify PGP signatures in artifact"

This reverts commit d92c82f87cef36cc6840b14b6d8e85be55f9f335.

Reason for revert: Build failure in I20210417-1800

Change-Id: Ieeb68052b0d9aa73f564d8eeb7f97f33bda6b6e8
Reviewed-on: https://git.eclipse.org/r/c/equinox/rt.equinox.p2/+/179035
Tested-by: Sravan Kumar Lakkimsetti <sravankumarl@in.ibm.com>
Reviewed-by: Sravan Kumar Lakkimsetti <sravankumarl@in.ibm.com>
44 files changed