Pull the TAB_API_URL from organization variables (#265)

This is configurable but not sensitive.

Author: jacebrowning

.github/workflows/ci.yml

@@ -74,7 +74,7 @@ jobs:
           npm run test:e2e
         env:
           VITE_API_TOKEN: ${{ secrets.KITTYCAD_API_TOKEN_DEV }}
-          TAB_API_URL: ${{ secrets.TAB_API_URL }}
+          TAB_API_URL: ${{ vars.TAB_API_URL }}
           TAB_API_KEY: ${{ secrets.TAB_API_KEY }}
           CI_COMMIT_SHA: ${{ github.event.pull_request.head.sha }}
           CI_PR_NUMBER: ${{ github.event.pull_request.number }}