Logger should clone objects before removing circular references.

[mbleigh]

Related issues

[REQUIRED] Version info

node:

firebase-functions:

firebase-tools:

firebase-admin:

[REQUIRED] Test case

[REQUIRED] Steps to reproduce

[REQUIRED] Expected behavior

[REQUIRED] Actual behavior

Were you able to successfully deploy your functions?

[inlined]

This was verified as WAI on March 15. Closing as no repro