JAXRS contract on API with @HeaderParam and @QueryParam cause feign client build fail

[bwangfdu]

Version 10.1.0
API definition:

@GET
    @Path("/orders/{externalOrderId}")
    @Produces({ "application/vnd.mycompany.application.order.v1+json", "application/vnd.mycompany.application.order+json", "application/vnd.mycompany.application.order.v2+json" })
    @ApiOperation(value = "Orders_GetOrderDetail", tags={  })
    @ApiResponses(value = { 
        @ApiResponse(code = 200, message = "OK", response = Order.class),
        @ApiResponse(code = 400, message = "Bad request", response = BadRequestResponseModel.class),
        @ApiResponse(code = 404, message = "Not Found", response = NotFoundResponseModel.class),
        @ApiResponse(code = 412, message = "Precondition Failed", response = PreconditionFailedModel.class),
        @ApiResponse(code = 500, message = "Internal Server Error", response = InternalErrorResponseModel.class) })
    public Order ordersGetOrderDetail(@PathParam("externalOrderId") String externalOrderId, @HeaderParam("Accept") String accept, @HeaderParam("Authorization") String authorization);

Error stack trace:

Caused by: java.lang.UnsupportedOperationException: null
	at java.base/java.util.Collections$UnmodifiableCollection.add(Collections.java:1058)
	at feign.jaxrs.JAXRSContract.addTemplatedParam(JAXRSContract.java:186)
	at feign.jaxrs.JAXRSContract.processAnnotationsOnParameter(JAXRSContract.java:165)
	at feign.Contract$BaseContract.parseAndValidateMetadata(Contract.java:110)
	at feign.jaxrs.JAXRSContract.parseAndValidateMetadata(JAXRSContract.java:44)
	at feign.Contract$BaseContract.parseAndValidatateMetadata(Contract.java:66)
	at feign.ReflectiveFeign$ParseHandlersByName.apply(ReflectiveFeign.java:154)
	at feign.ReflectiveFeign.newInstance(ReflectiveFeign.java:52)
	at feign.Feign$Builder.target(Feign.java:251)
	... 42 common frames omitted

This is caused by the Line 186 of JAXRSContract.java which trying to add an element into the template's headers or queries which become unmodified in 10.1.0, the previous version are not affected.
Can modify in JAXRSContract.java to make a new Collection instance and add new value then return it, wrapping unmodified if want to make accordance with feign-core.

[bwangfdu]

This is duplicate with #896