Simplify .cdsrc.json

- The `target: "."` is automatically coming with profile `java`
- The `java` profile is auto-assigned if a `pom.xml` is found

→ We can simplify the config here even further

.cdsrc.json

@@ -4,11 +4,5 @@
         "extensibility": true,
         "toggles": true
     },
-    "build": {
-        "target": "."
-    },
-    "profiles": [
-        "with-mtx-sidecar",
-        "java"
-    ]
+    "profile": "with-mtx-sidecar"
 }