Fix typo in documentation
A full-stop was missing in `TrustedHostMiddleware` section
Co-authored-by: Sebastián Ramírez <tiangolo@gmail.com>
The following arguments are supported:
-* `allowed_hosts` - A list of domain names that should be allowed as hostnames. Wildcard domains such as `*.example.com` are supported for matching subdomains to allow any hostname either use `allowed_hosts=["*"]` or omit the middleware.
+* `allowed_hosts` - A list of domain names that should be allowed as hostnames. Wildcard domains such as `*.example.com` are supported for matching subdomains. To allow any hostname either use `allowed_hosts=["*"]` or omit the middleware.
If an incoming request does not validate correctly then a `400` response will be sent.