Failures due to js engine 0.8.0

I try to implement the code from the oauth2-token-introspection-oss example, but the js code in the example has some failures since js engine 0.8.0.

line 22: <>.toBytes() does not exist anymore
line 38 and 39: reply.responseBody does not exist anymore

Can this be fixed (maybe more scripts have issues in this repo)