feat: add ToposCore upgrade test

[JDawg287]

Description

This PR includes a unit test for the upgrade feature of the ToposCore contract. The test involves pushing a certificate, upgrading the implementation contract, and then attempting to retrieve the same certificate post-upgrade. If successful, the test is considered passed.

Fixes TP-849

Additions and Changes

• Added the fetches the certificates from the contract after upgrade unit test in ToposCore.test.ts

PR Checklist:

• I have performed a self-review of my code
• I have commented on my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• I have added or updated tests that comprehensively prove my change is effective or that my feature works