chore: add why is this bad

crates/oxc_linter/src/rules/vitest/prefer_to_be_object.rs

@@ -40,6 +40,10 @@ declare_oxc_lint!(
     ///
     /// This rule enforce using `toBeObject()` when expect typeof `Object`.
     ///
+    /// ### Why is this bad?
+    ///
+    /// Using other methods such as `toBeInstanceOf(Object)` or `instanceof Object` can be less clear and potentially misleading. Enforcing the use of `toBeObject()` provides more explicit and readable code, making your intentions clear and improving the overall maintainability and readability of your tests.
+    ///
     /// ### Examples
     ///
     /// Examples of **incorrect** code for this rule: