Unable to create b-tree index more than 49 symbols length

Overview:

We need to create a b-tree index for loan agedToLostDelayedBilling.dateLostItemShouldBeBilled property, however it got rejected with Maximum fieldName length is 49: agedToLostDelayedBilling.dateLostItemShouldBeBilled.

Steps to Reproduce:

1. Declare a b-tree index (index) for a field where the field name length exceeds 49 symbols.
2. Run tenant initialization;

Expected Results:
B-tree index is created successfully.
Actual Results:
Error thrown com.fasterxml.jackson.databind.JsonMappingException: Maximum fieldName length is 49: agedToLostDelayedBilling.dateLostItemShouldBeBilled.

Task:
Extend schema.json to allow to set a shorter custom index name. RMB needs a unique index name to handle index creation, index recreation and index deletion. PostgreSQL truncates identifier names that are too long, this may result in a name clash.

Workaround:
Use a snippetPath .sql file to manually create a custom index name, see example in the comments.