Auto merge of #13722 - MariaSolOs:add-json-contrib, r=Veykril

Add VS Code schema validation for `rust-project.json`

Now that https://github.com/SchemaStore/schemastore/pull/2628 has been merged, adding the `jsonValidation` contribution to the VS Code extension for better editor support when modifying `rust-project.json` files.

Related issue: #13714

editors/code/package.json

@@ -1788,6 +1788,12 @@
                     "group": "navigation@1000"
                 }
             ]
-        }
+        },
+        "jsonValidation": [
+            {
+                "fileMatch": "rust-project.json",
+                "url": "https://json.schemastore.org/rust-project.json"
+            }
+        ]
     }
 }