Update how secrets are managed from Databricks secrets to Synapse way of managing secret (if required).

[devlace]

Description

Update how secrets are managed from Databricks secrets to Synapse way of managing secret (if required). In the original Parking Sensor sample, secrets are managed via Databricks KeyVault-backed secret scopes. This needs to be converted to "native" Synapse way of managing secrets.

DoD:

• [ ] Secrets (if any) are managed in Synapse using best practices.
• [ ] Managed identities are used where possible.

[jmostella]

@devlace Are we not considering using a KeyVault LinkedService?

[devlace]

KeyVault LinkedServices are def in consideration :) Just if we can use MSI, then even better.

[devlace]

This will get closed by #421