request help: the format of response body that returned by plugin should match Content-Type

Step 1 Create a route with consumer restriction

curl --location --request PUT ".../apisix/admin/routes/content-type" \
--header "X-API-KEY: edd1c9f034335f136f87ad84b625c8f1" \
--header "Content-Type: application/json" \
--data-raw "{
    \"methods\": [
        \"GET\"
    ],
    \"plugins\": {
        \"consumer-restriction\": {
            \"whitelist\": [
                \"nobody\"
            ]
        }
    },
    \"uri\": \"/content-type/get\"
}"

Step 2 Try to consume the route without being identified to raise an error I said i want application/json response :

curl --location --request GET ".../content-type/get" \
--header "Accept: application/json"

Response is :

# http code
401
# body 
{"message":"Missing authentication or identity verification."}
# In headers : 
Content-Type:  text/plain; charset=utf-8

The Content-Type header should be : application/json as it is in fact a Json in response.

This issue is not on "consumer-restriction"plugin only, it also happen for the key-auth plugin when you provide a wrong key, and i guess it is a .general plugin error behavior. I think it should exist a general common way to respond error from plugin to allow manage right content-type depending the response format. For example in case of a request like :

curl --location --request GET "..../content-type/get" \
--header "Accept: application/xml"

i expect a response like

# body 
<message>Missing authentication or identity verification.</message>
# In headers : 
Content-Type:  application/xml; charset=utf-8

---

In case of unknow accept or not managed, here we go for text/plain :

--header "Accept: */*"

Response should be something like :

# body 
Missing authentication or identity verification.
# In headers : 
Content-Type:  text/plain; charset=utf-8

Originally posted by @MekelCon in https://github.com/apache/apisix/discussions/8504#discussioncomment-4386548