Update content.md with additional preconnect

Update content.md with additional preconnect

When adding new fonts, Google Fonts now suggests adding both of the tags:

```
<link rel="preconnect" href="https://fonts.googleapis.com">
<link rel="preconnect" href="https://fonts.gstatic.com" crossorigin>
```

for example when adding: Lexend and Alegreya

```
<link rel="preconnect" href="https://fonts.googleapis.com">
<link rel="preconnect" href="https://fonts.gstatic.com" crossorigin>
<link href="https://fonts.googleapis.com/css2?family=Alegreya:ital,wght@0,400..900;1,400..900&family=Lexend:wght@100..900&display=swap" rel="stylesheet">
```