Use reference-style links in README

Author: guillermooo

README.md

@@ -1,7 +1,12 @@
 # PowerShell Editor Services
 
-[![CI Tests](https://github.com/PowerShell/PowerShellEditorServices/actions/workflows/ci-test.yml/badge.svg)](https://github.com/PowerShell/PowerShellEditorServices/actions/workflows/ci-test.yml)
-[![Discord](https://img.shields.io/discord/180528040881815552.svg?label=%23vscode&logo=discord&logoColor=white)](https://aka.ms/psdiscord)
+[![CI Tests][ci-tests-badge]][ci-tests-yaml]
+[![Discord][discord-badge]][discord]
+
+[ci-tests-badge]: https://github.com/PowerShell/PowerShellEditorServices/actions/workflows/ci-test.yml/badge.svg
+[ci-tests-yaml]: https://github.com/PowerShell/PowerShellEditorServices/actions/workflows/ci-test.yml
+[discord-badge]: https://img.shields.io/discord/180528040881815552.svg?label=%23vscode&logo=discord&logoColor=white
+[discord]: https://aka.ms/psdiscord
 
 **PowerShell Editor Services** is a PowerShell module that provides common
 functionality needed to enable a consistent and robust PowerShell development