Fix JS console error when COD is enabled and no shipping method is available.

[senadir]

Only return selected shipping methods from useSelectShippingRate, this fixes an issue with COD in which we try to see if user can make a payment based on the selected shipping method, the hook returned a broken object { 0: undefined } but it should have returned an empty object instead.

Fixes #2987

How to test the changes in this Pull Request:

1. Enable COD and limit it to a certain shipping method type.
2. Add that method to a certain address.
3. Select another address on the Checkout block, you shouldn't see an error with selectedMethod is undefined on the console.

Changelog

Fix JS console error when COD is enabled and no shipping method is available.

[github-actions]

Size Change: +19 B (0%)

Total Size: 1.11 MB

Filename	Size	Change
build/cart-frontend.js	69 kB	+4 B (0%)
build/cart.js	37.4 kB	+6 B (0%)
build/checkout-frontend.js	84.1 kB	+3 B (0%)
build/checkout.js	40.8 kB	+6 B (0%)

ℹ️ View Unchanged

Filename	Size	Change
build/active-filters-frontend.js	8.76 kB	0 B
build/active-filters.js	8.83 kB	0 B
build/all-products-frontend.js	31.2 kB	0 B
build/all-products.js	35.7 kB	0 B
build/all-reviews.js	9.76 kB	0 B
build/atomic-block-components/add-to-cart-frontend.js	8.89 kB	0 B
build/atomic-block-components/add-to-cart.js	7.46 kB	0 B
build/atomic-block-components/add-to-cart~atomic-block-components/button.js	3.16 kB	0 B
build/atomic-block-components/add-to-cart~atomic-block-components/image~atomic-block-components/title.js	335 B	0 B
build/atomic-block-components/button-frontend.js	2.02 kB	0 B
build/atomic-block-components/button.js	835 B	0 B
build/atomic-block-components/category-list-frontend.js	469 B	0 B
build/atomic-block-components/category-list.js	475 B	0 B
build/atomic-block-components/image-frontend.js	1.71 kB	0 B
build/atomic-block-components/image.js	1.15 kB	0 B
build/atomic-block-components/price-frontend.js	2.1 kB	0 B
build/atomic-block-components/price.js	2.13 kB	0 B
build/atomic-block-components/rating-frontend.js	524 B	0 B
build/atomic-block-components/rating.js	527 B	0 B
build/atomic-block-components/sale-badge-frontend.js	863 B	0 B
build/atomic-block-components/sale-badge.js	864 B	0 B
build/atomic-block-components/sku-frontend.js	389 B	0 B
build/atomic-block-components/sku.js	394 B	0 B
build/atomic-block-components/stock-indicator-frontend.js	568 B	0 B
build/atomic-block-components/stock-indicator.js	571 B	0 B
build/atomic-block-components/summary-frontend.js	918 B	0 B
build/atomic-block-components/summary.js	925 B	0 B
build/atomic-block-components/tag-list-frontend.js	466 B	0 B
build/atomic-block-components/tag-list.js	472 B	0 B
build/atomic-block-components/title-frontend.js	1.22 kB	0 B
build/atomic-block-components/title.js	1.05 kB	0 B
build/attribute-filter-frontend.js	18.1 kB	0 B
build/attribute-filter.js	12.4 kB	0 B
build/blocks.js	3.54 kB	0 B
build/editor-rtl.css	13.9 kB	0 B
build/editor.css	13.9 kB	0 B
build/featured-category.js	7.7 kB	0 B
build/featured-product.js	9.94 kB	0 B
build/handpicked-products.js	7.34 kB	0 B
build/price-filter-frontend.js	14.4 kB	0 B
build/price-filter.js	10.2 kB	0 B
build/product-best-sellers.js	7.42 kB	0 B
build/product-categories.js	3.23 kB	0 B
build/product-category.js	8.35 kB	0 B
build/product-new.js	7.58 kB	0 B
build/product-on-sale.js	7.96 kB	0 B
build/product-search.js	3.54 kB	0 B
build/product-tag.js	6.49 kB	0 B
build/product-top-rated.js	7.55 kB	0 B
build/products-by-attribute.js	8.29 kB	0 B
build/reviews-by-category.js	11.8 kB	0 B
build/reviews-by-product.js	13.3 kB	0 B
build/reviews-frontend.js	9.35 kB	0 B
build/single-product-frontend.js	34 kB	0 B
build/single-product.js	10.1 kB	0 B
build/style-rtl.css	18 kB	0 B
build/style.css	18 kB	0 B
build/vendors-style-rtl.css	1.03 kB	0 B
build/vendors-style.css	1.03 kB	0 B
build/vendors.js	416 kB	0 B
build/vendors~atomic-block-components/price-frontend.js	5.65 kB	0 B
build/wc-blocks-data.js	7.09 kB	0 B
build/wc-blocks-middleware.js	931 B	0 B
build/wc-blocks-registry.js	2.28 kB	0 B
build/wc-payment-method-bacs.js	790 B	0 B
build/wc-payment-method-cheque.js	787 B	0 B
build/wc-payment-method-cod.js	875 B	0 B
build/wc-payment-method-paypal.js	831 B	0 B
build/wc-payment-method-stripe.js	11.9 kB	0 B
build/wc-settings.js	2.33 kB	0 B
build/wc-shared-context.js	1.53 kB	0 B
build/wc-shared-hocs.js	1.66 kB	0 B

_{compressed-size-action}

[Aljullu]

This solution looks good to me. 👍

If I understand it correctly, that means selectedShippingRates will only contain packages that have a selected shipping rate, correct? Do you think we could add this info to the doc comment above useSelectShippingRate? I feel this area might be confusing so maybe it's better to explicitly explain it.