[saas-microservices] Fix turbo build caching configuration (#1192)

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### Type of Change

- [ ] New Example
- [ ] Example updates (Bug fixes, new features, etc.)
- [ ] Other (changes to the codebase, but not to examples)

### New Example Checklist

- [ ] 🛫 `npm run new-example` was used to create the example
- [ ] 📚 The template wasn't used but I carefuly read the [Adding a new
example](https://github.com/vercel/examples#adding-a-new-example) steps
and implemented them in the example
- [ ] 📱 Is it responsive? Are mobile and tablets considered?

Author: mknichel

solutions/saas-microservices/apps/api-dashboard/turbo.json

@@ -0,0 +1,9 @@
+{
+  "extends": ["//"],
+  "tasks": {
+    "build": {
+      "cache": false,
+      "outputs": [".nitro/**", ".vercel/**"]
+    }
+  }
+}

solutions/saas-microservices/apps/api-users/turbo.json

@@ -0,0 +1,9 @@
+{
+  "extends": ["//"],
+  "tasks": {
+    "build": {
+      "cache": false,
+      "outputs": [".vercel/**"]
+    }
+  }
+}