Update class-wc-frontend-scripts.php

See also https://github.com/bassjobsen/wp-defer-loading/issues/14 prettyPhoto-init is not only dependent of jquery, but also of prettyPhoto. The dependency of prettyPhoto is not set.
removed wc_clean/sanitize_text_field not needed. handled by wp core functions fixes #5318
added method to stop save duplicate sku in quick edit
fixed coding standards in includes/admin/post-types/class-wc-admin-cpt-product.php
Removes unused block and var.

There's duplicate block that does the same thing, but assigning to different variable.
On the end only the last variable is used, which is `$username`.
Update class-wc-emails.php

Check for a value against each meta item before outputting.
Typo fix.
fixed my account downloadables out of order
fixed incorrect order received endpoit tooltip
Update class-wc-admin-cpt-product.php

To handle bulk edit of "Sold Individually".
(The view part will follow in the next edit)
Update html-bulk-edit-product.php

The view part of "Sold Individually" bulk edit
Docblock fix: wc_product_post_type_link
Merge pull request #5308 from maxrice/master

Update REST API documentation link
Merge pull request #5317 from bassjobsen/patch-3

Update class-wc-frontend-scripts.php
Merge pull request #5321 from claudiosmweb/fix-quick-edit-duplicate-sku

Prevent duplicate sku when edit product using quick edit
Merge pull request #5327 from gedex/typo-fix

Typo fix.
Merge pull request #5325 from gedex/refactor_cpt-shop_order_custom_columns

Removes unused block and var.
Merge pull request #5326 from christian-thomas/patch-1

Update class-wc-emails.php
Merge pull request #5330 from splashingpixels/downloads-order-my-account

fixed my account downloadables out of order
Merge pull request #5331 from corsonr/settings-tooltip

fixed incorrect "order received" endpoint tooltip