Update bitcoinjs-lib dependency to the latest version (from v3.3.1 to v6.0)

[motorina0]

Currently bolt11 uses bitcoinjs-lib v3.3.1. This is a very old version.

The API used from bitcoinjs-lib is:

• toBase58Check()
• fromBase58Check()
• toBech32()
• fromBech32()

Please let me know if it is OK to:

• update to the latest bitcoinjs-lib version (6.0)
• bump the version of this lib to 1.3.3 (from 1.3.2)

If yes, then I will open a PR with the changes.

[junderw]

This can also allow fallback address to be segwit v1 as well, and remove the dependency on tiny-secp256k1.

Yes this would be a good change I think.