* feat: Add support for brands (#918)
* feat: add product brand support with where args, taxonomy filter, and taxonomy mutation input fields
- Register product_brand taxonomy with WPGraphQL (fix indentation from #964)
- Add productBrand/productBrandIn/productBrandNotIn/productBrandId/productBrandIdIn/productBrandIdNotIn
where args on products connection
- Add product_brand to taxonomy args map and case statements in product connection resolver
- Register additional input fields (display, menuOrder, imageId) on
CreateProductCategoryInput and UpdateProductCategoryInput mutations
- Split ProductTaxonomyQueriesTest into ProductCategoryQueriesTest,
ProductTagQueriesTest, ProductCategoryMutationsTest, ProductTagMutationsTest
- Add ProductBrandQueriesTest with 8 tests covering queries, connections,
hierarchy, where args, taxonomy filter, and CRUD mutations
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Co-authored-by: Geoff Taylor <geoff@axistaylor.com>
