`MessageTypeParser.parseMessageType()` Fails to Parse Valid Parquet Schemas with Special Characters in Field Names

### Describe the bug, including details regarding any error messages, version, and platform.

The MessageTypeParser.parseMessageType(String) method fails when parsing Parquet schemas containing field names with special characters such as "name=id" or "first name". These field names are valid in Parquet schema definitions and Parquet files successfully support them. However, parseMessageType throws an error or fails to deserialize such schemas back into a valid MessageType object.

Steps to Reproduce:
Create a valid Parquet schema with a field name like name=id or first name.
Convert it to a string using .toString().
Attempt to parse it back using MessageTypeParser.parseMessageType(parquetSchema.toString()).

Suggested Fix:
Enhance MessageTypeParser to properly handle and deserialize field names containing special characters, ensuring compliance with the Parquet specification.

### Component(s)

_No response_

Beginne mit MessageTypeParser.parseMessageType(String) und reproduziere den Roundtrip mithilfe eines gültigen Parquet-Schemas, dessen Feldname "name=id" oder "first name" enthält. Als abgeschlossen gilt dies, wenn der von toString() erzeugte Schema-String wieder in einen äquivalenten gültigen MessageType ohne Fehler geparst wird.

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