Fix: inference on multiline csv schema

[bongjunj]

This resolves the point raised at #1483 (comment) by @nightroman

• Defined a dedicated function to read schema string to break it down into strings, separated by comma, skipping newline characters (CR/LF).
• Used ResizeArray to build an array of strings, so .Length changed to .Count when used.

[cartermp]

Thanks, sorry for delay in review here!