Change deprecated method is_graphql_request

[fabiojundev]

Method WPGraphQL\Router::is_graphql_request to WPGraphQL\Router::is_graphql_http_request

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What does this implement/fix? Explain your changes.

This PR only changes one method to another the suggested one.
WPGraphQL\Router::is_graphql_request is deprecated since 0.4.1. Use Router::is_graphql_http_request instead.
https://github.com/wp-graphql/wp-graphql/blob/develop/src/Router.php#L220

Does this close any currently open issues?

No

Any relevant logs, error output, GraphiQL screenshots, etc?

(If it’s long, please paste to https://ghostbin.com/ and insert the link here.)

Any other comments?

…

Where has this been tested?

• WooGraphQL Version: 0.11.2
• WPGraphQL Version: 1.12.2
• WordPress Version: 6.1
• WooCommerce Version: 7.1.0