Hoxton.SR6 with Spring Boot 2.3.0 cause weird content type issue

When i updated my Spring Boot 2.3.0.RELEASE Application from Hoxton.SR4 to Hoxton.SR6 (the only change), i started facing weird issues with Content Type from various endpoints.

For example, with Hoxton.SR4, any unauthorized endpoint was returning this error:

{
   "error": "unauthorized",
   "error_description": "Full authentication is required to access this resource"
}

Same authorization server error in Hoxton.SR6 comes in XML

<UnauthorizedException>
     <error>unauthorized</error>
     <error_description>Full authentication is required to access this resource</error_description>
</UnauthorizedException>

many other endpoints are returning content in XML rather than application/json.

Can someone help with fixing the default content type for Spring Cloud Hoxton.SR6?