Link to Breaking changes best practices

Author: dcrossleyau

guidelines/index.md

@@ -33,6 +33,7 @@ See other orientation [guides](/guides/#background-orientation).
 
 - [Guidelines for Contributing Code](contributing/).
 - [Naming conventions](naming-conventions/).
+- [Breaking changes best practices](https://folio-org.atlassian.net/wiki/x/VQBTR).
 - [Development, design, and review processes](development-design-review/).
 - [Pull requests checklists](pull-requests-checklists/).