Charset at Multipart Form header

[fkesheh]

According to this discussion thread https://github.com/SpiderLabs/ModSecurity/issues/1900 having a charset= parameter in that Content-Type header appears to be contrary to the standard, so ModSecurity is blocking it.

Feign add it by default:

https://github.com/OpenFeign/feign-form/blob/98e51d187f1b7acba3b39d1131371b761d87259b/feign-form/src/main/java/feign/form/MultipartFormContentProcessor.java#L94

Could that become optional or configurable?