Fix assume role for the fresh account

[nikpodsh]

New accounts doesn't have cdk-hnb659fds-lookup-role it leads to issue

Implementation details:
According to description of

For first deployments it returns False,
for existing deployments it returns the ssm parameter value generated in the first deployment
for prior to V1.5.1 upgrades it returns the secret from secrets manager

For first deployments it fails because there is no role to assume

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