Allow for bigint values in JSON.stringify

[jacogr]

This change is as the result of a CI failure where bigint values are in-use -

https://github.com/LedgerHQ/ledger-live-desktop/runs/4325584600?check_suite_focus=true#step:13:92

Some background reading here - https://dev.to/benlesh/bigint-and-json-stringify-json-parse-2m8p

In this approach instead of adding a replacer, the typeof is just checked and then toString() is used on the value if found to be a bigint.