public GrpcExceptionHandlerFunctionBuilder on(Class<? extends Throwable> exceptionType, Status status) {
        requireNonNull(status, "status");
        return on(exceptionType, (ctx, unused, cause, metadata) -> status);
    }
Adds the specified exception mapping that maps a {@link Throwable} to a gRPC {@link Status}.
The mapping is used to handle a {@link Throwable} when it is raised.
grpc/src/main/java/com/linecorp/armeria/common/grpc/GrpcExceptionHandlerFunctionBuilder.java