Use dedicated repos for @kadence packages

[oakesjosh]

We're increasingly running into instances where components between free and pro differ since they are separate codebases. This duplicates the setup used in blocks pro where packages are added as submodules at /src/packages/ from their repos (kadence-icons, kadence-helpers, kadence-components)

Merging into nav so we have adequate testing and this can be part of a point release. The main risk with this is if there's changes that exist in the kadence-blocks repo for a component, that hadn't been updated in the kadence-components repo. I've done an initial check for this, but will do a second pass.

Other changes

• Added an .npmrc file so we don't have to manually set --legacy-peer-deps on npm installs
• Remove call to deprecated webpack function in StyleOnlyEntryPlugin
• Removed unused reference to PexelsIcon. The icon does not exist

Eventually, it'd be nice to include these as packages instead of submodules. This will add some overhead to local development and updating components though.