Support other KMS providers (e.g. AWS)

Issue To Be Solved

Currently the Flow CLI only supports Google KMS.

Example:

...
"accounts": {
  "admin-account": {
    "address": "service",
    "key": {
        "type": "google-kms",
        "index": 0,
        "signatureAlgorithm": "ECDSA_P256",
        "hashAlgorithm": "SHA3_256",
        "resourceID": "projects/flow/locations/us/keyRings/foo/bar/cryptoKeyVersions/1"
    }
  }
}
...

You can also use a key management system (KMS) to sign the transactions. Currently, we only support Google KMS.

(Optional): Suggest A Solution

Add support for other KMS providers (e.g. aws-kms, azure-kms, etc), or provide sample on docs that shows workaround for other KMS providers if functionality already exists.

(Optional): Context

Requested on Discord