Replace "blacklist/whitelist" terminology in code comments, and internal variable, method and class names

[tlfeng]

Is your feature request related to a problem? Please describe.
Replace "blacklist/whitelist" terminology in the code base, but only the places that won't impact the backwards compatibility.

A part of #1483

Describe the solution you'd like
Replace all the "blacklist/whitelist" terminology with "denylist/allowlist" in the following location:

• code comments
• Internal variable, method and class names

Any APIs or configurations will not be impacted.

Describe alternatives you've considered
None.

Additional context
None.