* Rename `provider` to `providerConfig`
The network controller `provider` state has been renamed to
`providerConfig`. This better reflects what this state is, and makes
this controller more closely aligned with the core network controller.
All references to the provider configuration have been updated to
prefer `providerConfig` over `provider`, to make the distinction clear
between a provider and provider config.
Closes#18902
* Add migration
* prepare for EIP1559 gas fields in speedup/cancel
* Update ui/components/app/gas-customization/gas-modal-page-container/gas-modal-page-container.container.js
