TaxRate connection improvements

[kidunot89]

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What does this implement/fix? Explain your changes.

• Adds postCode and postCodeIn whereArgs to the taxRates query.

Example Usage

query ( $class: TaxClassEnum, $postCode: String, $postCodeIn: [String] ) {
	taxRates( where: { class: $class, postCode: $postCode, postCodeIn: $postCodeIn } ) {
		nodes {
			id
		}
	}
}

WhereArgs Definition

'class'      => array(
	'type'        => 'TaxClassEnum',
	'description' => __( 'Sort by tax class', 'wp-graphql-woocommerce' ),
),
'postCode'   => array(
	'type'        => 'String',
	'description' => __( 'Filter results by a post code.', 'wp-graphql-woocommerce' ),
),
'postCodeIn' => array(
	'type'        => array( 'list_of' => 'String' ),
	'description' => __( 'Filter results by a group of post codes', 'wp-graphql-woocommerce' ),
),
'orderby'    => array(
	'type'        => array( 'list_of' => 'TaxRateConnectionOrderbyInput' ),
	'description' => __( 'What paramater to use to order the objects by.', 'wp-graphql-woocommerce' ),
),

Does this close any currently open issues?

#105

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?

Operating System: Linux Mint 19.2

WordPress Version: 5.3.2