Update badges

Author: gkellogg

README.md

@@ -2,7 +2,7 @@
 
 This is a [Ruby][] implementation of [LD Patch][] for [RDF.rb][].
 
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 [![Build Status](https://github.com/ruby-rdf/ld-patch/workflows/CI/badge.svg?branch=develop)](https://github.com/ruby-rdf/ld-patch/actions?query=workflow%3ACI)
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