Improve clarity of a sentence in the "Lifecycle Hooks" section of the docs (#1597)

* Update lifecycle.md

* Update lifecycle.md

Author: jonksc

src/guide/essentials/lifecycle.md

@@ -51,7 +51,7 @@ setTimeout(() => {
 }, 100)
 ```
 
-Do note this doesn't mean that the call must be placed lexically inside `setup()` or `<script setup>` - `onMounted()` can be called in an external function as long as the call stack is synchronous and originates from within `setup()`.
+Do note this doesn't mean that the call must be placed lexically inside `setup()` or `<script setup>`. `onMounted()` can be called in an external function as long as the call stack is synchronous and originates from within `setup()`.
 
 </div>