Change highlight.js/vue to peerDependencies to enforce versions (#17)

Author: Trinovantes

package.json

@@ -20,7 +20,7 @@
     "tslib": "^2.2.0",
     "typescript": "^4.2.4"
   },
-  "dependencies": {
+  "peerDependencies": {
     "highlight.js": "^11.0.1",
     "vue": "^3"
   },