[BUG] - When the client sets accept:text/event-stream then response not supported

[chengyouling]

Steps to Reproduce

1. produceProcessorMap add init text/event-stream processor.
2. using ProduceJsonProcessor parse respone when text/event-stream request failed.

Expected Behavior

No response

Servicecomb Version

2.9.0

Additional Context

No response

[liubao68]

Which version do you find this problem and which versions are effected? And how to reproduce this problem?

[chengyouling]

Steps to Reproduce:

1. produceProcessorMap add init text/event-stream processor.
2. using ProduceJsonProcessor parse respone when text/event-stream request failed.

version: 2.9.x

And please help review the corresponding PR, ths. @liubao68