fix: remove unused github action

.github/workflows/readme.yaml

@@ -1,18 +0,0 @@
-name: Sync OAS to ReadMe
-on:
-  push:
-    branches:
-      - master
-      - main
-jobs:
-  build:
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@v2
-      - uses: readmeio/github-readme-sync@v2
-        with:
-          readme-oas-key: oDf7vsdkbfuFmj6M7E5W98QcmyBnLpmM:5fc4b9a323e95041cd0a08fb
-           
-          # OPTIONAL CONFIG, use if necessary
-          # oas-file-path: './swagger.json'
-          # api-version: 'v1.0.0'

docs/api/oas/openapi.yaml

@@ -60,7 +60,7 @@ info:
     Alternatively, you can test the API in [Postman](https://app.getpostman.com/run-collection/8552ddcd4cc9fc012548)
 
     [![Run in Postman](https://run.pstmn.io/button.svg)](https://app.getpostman.com/run-collection/8552ddcd4cc9fc012548)
-  version: 3.5.6
+  version: 3.7.0
   contact:
     name: The Unleash team
     url: 'https://unleash.github.io/'