fix: use contractions in Safari warnings per Vale linting

Co-Authored-By: Colton Berry <[email protected]>

Author: devin-ai-integration[bot]

fern/products/docs/pages/component-library/default-components/embed.mdx

@@ -13,7 +13,7 @@ Fern also implements a custom component for embedding downloadable assets:
 - `<Download src="..." />` - read more about it [below](#downloadable-assets).
 
 <Warning>
-  The `<embed>` component is not well-supported on Safari and may cause compatibility issues. For embedding videos, use the `<video>` component instead, which provides better cross-browser support and more control over playback.
+  The `<embed>` component isn't well-supported on Safari and may cause compatibility issues. For embedding videos, use the `<video>` component instead, which provides better cross-browser support and more control over playback.
 </Warning>
 
 ## Properties
@@ -43,7 +43,7 @@ Fern also implements a custom component for embedding downloadable assets:
     ```
 
     <Warning>
-        The `<embed>` component is not well-supported on Safari and may cause compatibility issues. For embedding videos, use the [`<video>` component](/learn/docs/content/write-markdown#embedding-videos) instead, which provides better cross-browser support and more control over playback. Additionally, videos with audio will automatically play when the page loads with `<embed>`.
+        The `<embed>` component isn't well-supported on Safari and may cause compatibility issues. For embedding videos, use the [`<video>` component](/learn/docs/content/write-markdown#embedding-videos) instead, which provides better cross-browser support and more control over playback. Additionally, videos with audio will automatically play when the page loads with `<embed>`.
     </Warning>
 
   </Tab>

fern/products/docs/pages/component-library/writing-content/markdown.mdx

@@ -121,7 +121,7 @@ For example, to embed a video, use the following Markdown:
 <embed src="./embed-fern-waving.mp4" type="video/mp4" width="640px" height="360px" />
 
 <Warning>
-  The `<embed>` component is not well-supported on Safari and may cause compatibility issues. For embedding videos, use the `<video>` component instead (see below), which provides better cross-browser support and more control over playback.
+  The `<embed>` component isn't well-supported on Safari and may cause compatibility issues. For embedding videos, use the `<video>` component instead (see below), which provides better cross-browser support and more control over playback.
 </Warning>
 
 ### Local videos