Declare inversify as peerDependency

Author: kaisalmen

packages/sprotty/package.json

@@ -51,10 +51,12 @@
     "url": "https://github.com/eclipse/sprotty",
     "directory": "packages/sprotty"
   },
+  "peerDependencies": {
+    "inversify": "~6.0.1"
+  },
   "dependencies": {
     "autocompleter": "^7.0.1",
     "file-saver": "^2.0.5",
-    "inversify": "~6.0.1",
     "snabbdom": "^3.5.1",
     "sprotty-protocol": "^0.13.0",
     "tinyqueue": "^2.0.3"