Update README.md

Author: juddmehr

README.md

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 # OptimizationParameters
 
 [![Dev](https://img.shields.io/badge/docs-dev-blue.svg)](https://flow.byu.edu/OptimizationParameters.jl/dev)
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+[![Build Status](https://github.com/byuflowlab/OptimizationParameters.jl/actions/workflows/CI.yml/badge.svg?branch=master)](https://github.com/byuflowlab/OptimizationParameters.jl/actions/workflows/CI.yml?query=branch%3Amaster)
 
 *Convenient optimization framework parameter manipulation in Julia*