[IMPROVEMENT] withRetries should not affect other calls

[pcsiszar-bw]

As the current implementation stands, calling withRetries on the Vault object modifies the retry logic for all subsequent calls to Vault, unless they specifically override it using withRetries in their own call.

I'd like it if withRetries would only affect the call being made and not any other ones that follow after.

It also is a bit of a code smell that the VaultConfig final object gets manipulated using the withRetries call. I propose withRetries returns a new RetryingVault (or similar) interface, and move that holds the parameters for a retry in it's own implementation, and passes a copy of Vault Config extended with the retry parameters to the Logical, Auth, and other dsl classes that would rely on it.