`async-mutex` is now imported using `import` rather than `require`.
This ensures that TypeScript is type checking our usage of the module,
rather than typing it as `any`.

No other changes were required.

`async-mutex` is now imported using `import` rather than `require`.
This ensures that TypeScript is type checking our usage of the module,
rather than typing it as `any`.

No other changes were required.

…) package (#401)

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## Explanation

The newly created EIP-5792 Middleware package ([PR
#6422](#6422)) currently contains
only the hooks required for the existing wallet middleware. To align
with the intended abstraction and reduce the monolithic nature of
wallet-middleware, we should fully extract the relevant middleware logic
from eth-json-rpc-middleware ([GitHub -
MetaMask/eth-json-rpc-middleware: Ethereum middleware for composing an
Ethereum provider using json-rpc-engine. Intended to replace
provider-engine](https://github.com/MetaMask/eth-json-rpc-middleware))
into this new package.

This PR removes the identified middleware into
@metamask/eip-5792-middleware.

PR [#6477](#6477) from
https://github.com/MetaMask/core moves this middleware to the specified
package.

* Fixes https://consensyssoftware.atlassian.net/browse/WAPI-691