chore: remove insomnia

this was just for the tutorial and we dont need it forever.

openapi.yaml

@@ -9,12 +9,6 @@ info:
     Experiment with this API in Postman, using our Postman Collection.
 
     [<img src="https://run.pstmn.io/button.svg" alt="Run In Postman" style="width: 128px; height: 32px;">](https://app.getpostman.com/run-collection/9265903-7a75a0d0-b108-4436-ba54-c6139698dc08?action=collection%2Ffork&source=rip_markdown&collection-url=entityId%3D9265903-7a75a0d0-b108-4436-ba54-c6139698dc08%26entityType%3Dcollection%26workspaceId%3Df507f69d-9564-419c-89a2-cb8e4c8c7b8f)
-
-    ## Run in Insomnia
-
-    Experiment with this API in Insomnia, using our Insomnia Collection.
-    
-    [![Run in Insomnia}](https://insomnia.rest/images/run.svg)](https://insomnia.rest/run/?label=Train%20Travel%20API&uri=https%3A%2F%2Fraw.githubusercontent.com%2Fbump-sh-examples%2Ftrain-travel-api%2Fmain%2Finsomnia%2FInsomnia_2024-05-27.json)
   version: 1.0.0
   contact:
     name: Train Support
@@ -23,6 +17,9 @@ info:
   license: 
     name: Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International
     identifier: CC-BY-NC-SA-4.0
+  x-feedbackLink:
+    label: Submit Feedback
+    url: https://github.com/bump-sh-examples/train-travel-api/issues/new
 
 servers:
   - url: https://api.example.com