feat: add optional auto-approve config on no approver

[edwinkys]

Description

Fixes #22

This PR allows users to optionally configure to auto approve all approver request received by the system when in case there is no approver available. This configuration is great for small team but not recommended in production.

How Has This Been Tested?

• New and existing unit tests pass locally with my changes.
• I have added tests that prove my changes are working as expected.

I have tested my work by:

1. Running the server with auto approval configuration active.
2. Emulate a get approval method
3. Without any approver connected the auto approval should approve the request.

Checklist

• I have performed a self-review of my own code.
• I have commented my code, particularly in hard-to-understand areas.
• I have made corresponding changes to the documentation.