Update README.md

Author: ChrisRackauckas

README.md

@@ -2,7 +2,6 @@
 
 [![Stable](https://img.shields.io/badge/docs-stable-blue.svg)](https://docs.sciml.ai/ArrayInterface/stable/)
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-[![CI (Julia nightly)](https://github.com/JuliaArrays/ArrayInterface.jl/workflows/CI%20(Julia%20nightly)/badge.svg)](https://github.com/JuliaArrays/ArrayInterface.jl/actions?query=workflow%3A%22CI+%28Julia+nightly%29%22)
 [![Build status](https://badge.buildkite.com/a2db252d92478e1d7196ee7454004efdfb6ab59496cbac91a2.svg?branch=master)](https://buildkite.com/julialang/arrayinterface-dot-jl)
 [![codecov](https://codecov.io/gh/JuliaArrays/ArrayInterface.jl/branch/master/graph/badge.svg)](https://codecov.io/gh/JuliaArrays/ArrayInterface.jl)