Merge pull request #75 from Gusto/raquel/GWS-5560/slack-webhook-url

[GWS-5560] add slack webhook url to notify of speakeasy build failures

Author: rqsilva

.github/workflows/sdk_generation.yaml

@@ -31,3 +31,4 @@ jobs:
       npm_token: ${{ secrets.NPM_TOKEN }}
       openapi_doc_auth_token: ${{ secrets.OPENAPI_DOC_AUTH_TOKEN }}
       speakeasy_api_key: ${{ secrets.SPEAKEASY_API_KEY }}
+      slack_webhook_url: ${{ secrets.SLACK_WEBHOOK_URL }}