Add support for PUT in Client API

[omitech]

The LinkedIn Assets API uses the PUT method to upload image assets, but the current implementation does not support it for the following reasons:

• The PUT method does not return any response body, making it incompatible with Client::api, which expects a response body.
• The Method::isMethodSupported currently prohibits the PUT method.

Added Client::put($endpoint, $resource) to handle uploads:

Parameters:

• $endpoint (string): The API endpoint where the resource will be sent.
• $resource (resource): The data resource to be uploaded (typically a file handle).

If the provided argument is not a valid resource, it throws an InvalidArgumentException