Update risk bank variable name for Granite Guardian 3.2 use

[evaline-ju]

The area of code described is not actively invoked for Granite Guardian but will lead to problems for Granite Guardian 3.2 if invoked. Currently here the RISK_BANK_VAR_NAME is defined as risk_bank, but the corresponding variable in the 3.2 chat template is risk_types as noted in the outcomes of #56 . If the chat template is to be parsed, the RISK_BANK_VAR_NAME will have to be updated (either statically, or potentially dynamically).