fix(docs): only rewrite relative links (#3339)

Fixes #3147

Author: devversion

Diff for: tools/gulp/tasks/docs.ts

@@ -82,7 +82,9 @@ function transformMarkdownFiles(buffer: Buffer, file: any): string {
 
 /** Fixes paths in the markdown files to work in the material-docs-io. */
 function fixMarkdownDocLinks(link: string, filePath: string): string {
-  if (link.startsWith('http') && filePath.indexOf('guides/') === -1) {
+  // As for now, only markdown links that are relative and inside of the guides/ directory
+  // will be rewritten.
+  if (!filePath.includes(path.normalize('guides/')) || link.startsWith('http')) {
     return link;
   }