Adds NO_QL_SESSION_HANDLER flag

[kidunot89]

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What does this implement/fix? Explain your changes.

When set to a truthy value. WooCommerce falls back to the default session handler during GraphQL requests. This is meant to allow for use of cookie sessions managed by WC_Session_Handler instead of the custom session header managed by the QL_Session_Handler class (the default) during GraphQL requests.

Example usage

define( 'NO_QL_SESSION_HANDLER', true);

Does this close any currently open issues?

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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?

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Where has this been tested?

Operating System: Ubuntu 18.04

WordPress Version: 5.2