Feature/identity key management

[DmyMi]

A possible fix for Microsoft.IdentityModel.Tokens.SecurityTokenSignatureKeyNotFoundException: IDX10501: Signature validation failed and constant 401 status codes caused by using developer credentials (that are stored as local file per instance and are randomly generated each time instance cold starts) in our staging ephemeral distributed environment.

• 👍 Simplified solution that does not require third party services, i.e. Vault or any other KMS
• 👍 Simple interface that can be backed by aforementioned Vault later if needed.
• 👍 Simple key expiration handling
• 👍 Concurrency friendly creation & update - tested with 100 concurrent requests and 20 seconds certificate expiration to simulate key rotation.
• 👍 Should work in distributed environment (need to test)
  Cons:
• 👎 Having more than 1 certificate at a given time is not implemented. So we have "hard" key rotation (If key is rotated, i.e. once a week, all tokens become invalid & and need to re-login).
• 👍 Cheaper than Identity Server paid solution :)

TODO: tests

[sonarqubecloud]

SonarCloud Quality Gate failed.   

0 Bugs
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0 Security Hotspots
9 Code Smells

0.0% Coverage
0.0% Duplication