fix: incorrect link to Material source code

Author: gkanishk

README.md

@@ -26,7 +26,7 @@ The guides, examples, and docs content repo
 [angular/material2-docs-content](https://github.com/angular/material2-docs-content) contains the
 documentation content and examples. They are generated from:
 - [Angular Material and CDK Guides](https://github.com/angular/components/tree/master/guides)
-- [Material components, services, and directives](https://github.com/angular/components/tree/master/src/lib)
+- [Material components, services, and directives](https://github.com/angular/components/tree/master/src/material)
 - [CDK components, services, and directives](https://github.com/angular/components/tree/master/src/cdk)
 
 ## Development Setup