Automatically reopen closed secret scanning alerts if the validity becomes active

[decyjphr]

Description:
Automatically reopen closed secret scanning alerts if the validity for the secret changes from unknown or inactive to active
Add a comment to the alert to indicate why it is being reopened
Note: This change would likely require changes to Fidelity's Compliance App too to ensure that developers can't close these alerts if they are reopened, as currently if a developer was granted access to bypass push protections they are not prevented from closing the alert.