ci: replace WEB_DEFAULT_API var with dummy

why was this a variable wtf

.github/workflows/test.yml

@@ -25,7 +25,7 @@ jobs:
       - uses: pnpm/action-setup@v4
       - run: .github/test.sh web
         env:
-          WEB_DEFAULT_API: ${{ vars.WEB_DEFAULT_API }}
+          WEB_DEFAULT_API: https://api.dummy.example/
 
   test-api:
     name: api sanity check
@@ -33,4 +33,4 @@ jobs:
     steps:
       - uses: actions/checkout@v4
       - uses: pnpm/action-setup@v4
-      - run: .github/test.sh api
+      - run: .github/test.sh api