DEVDOCS-6693 - Fix typo in GraphQL Storefront API Tokens Spec (#1224)

<!-- Ticket number or summary of work -->
# [DEVDOCS-6692]


## What changed?
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* Fixed typo in GraphQL Storefront API Tokens Spec

## Release notes draft
This PR does not need to be included in the release notes

ping  @bigcommerce/dev-docs 


[DEVDOCS-6692]:
https://bigcommercecloud.atlassian.net/browse/DEVDOCS-6692?atlOrigin=eyJpIjoiNWRkNTljNzYxNjVmNDY3MDlhMDU5Y2ZhYzA5YTRkZjUiLCJwIjoiZ2l0aHViLWNvbS1KU1cifQ

Author: chris-nowicki

reference/storefront_tokens.v3.yml

@@ -17,7 +17,7 @@ info:
     This special token is not necessary if you only wish to query information from an anonymous shopper's perspective.
 
     > #### Warning
-    > Unless your frontend client proxies requests, attempts to authenticate from the brower using customer impersonation tokens will be rejected.
+    > Unless your frontend client proxies requests, attempts to authenticate from the browser using customer impersonation tokens will be rejected.
 
     ## Additional information