[SUPPORT] Cannot create numer field name

[muyihao]

Describe the problem you faced

Is Hudi considering supporting numeric field names? In version 0.14, the table schema is still based on Avro format. If a field name starts with a number, such as "19", there is an exception when creating the table because Avro does not support field names that start with a number.

[rangareddy]

Hudi doesn't support column names starting with integer as avro schema validation will fail for this.

Please refer the 10553 issue for more details.