Ignore [[...slug]].mdx in Crowdin (#375)

Author: benface

crowdin.yml

@@ -4,6 +4,8 @@ files:
     translation: /website/pages/%two_letters_code%/**/%original_file_name%
     dest: /**/%original_file_name%
     content_segmentation: 0
+    ignore:
+      - /website/pages/en/substreams/[[...slug]].mdx
   - source: /website/pages/en/**/*.json
     translation: /website/pages/%two_letters_code%/**/%original_file_name%
     dest: /**/%original_file_name%