synapse PAT access

[alexpaynter]

This is a suggestion for a feature - not a bug!

Synapse generally recommends access via personal access tokens due to the controlled permissions they give (e.g. you can't change a password). I think this would be a relatively simple extension to your current use of the synapse REST API (https://rest-docs.synapse.org/rest/) via httr in https://github.com/GENIE-BPC/genieBPC/blob/main/R/synapse_authentication.R.