Revert "Add snapshot repository so modernizer doesn't fail."

This reverts commit c80849a711126bbd3493177812e2328ab7ac2a83. The
snapshot repository has now been added to the jclouds-project POM.

See https://github.com/jclouds/jclouds/commit/79d4b48d0151667db062a7035b23b28d7a1e1daf