deps: perform yarn upgrade

The commit performs a `yarn upgrade` to resolve a known vulnerability
with `engine.io`. The changes also better reflect what downstream
dependents will pull when they build their own Theia-based products.

Signed-off-by: vince-fugnitto <vincent.fugnitto@ericsson.com>

Author: vince-fugnitto

packages/core/package.json

@@ -54,7 +54,7 @@
     "lodash.debounce": "^4.0.8",
     "lodash.throttle": "^4.1.1",
     "markdown-it": "^12.3.2",
-    "msgpackr": "^1.6.1",
+    "msgpackr": "~1.8.3",
     "nsfw": "^2.2.4",
     "p-debounce": "^2.1.0",
     "perfect-scrollbar": "^1.3.0",