Fixed maximum length of route metadata

[GooDer]

Fixed maximum length of route metadata

Motivation:

I encountered problem in our project where we are using rsocket to communication with Java server.
We have for some legacy reason very long URL path to Java endpoint which is around 138 characters long.

>           serialized += struct.pack('>b', len(tag))
E           struct.error: byte format requires -128 <= number <= 127

In this case the rsocket throw error on preparation of length byte for the tag. From the code I believe that the intention was to allow size of 0 - 255 but right now it is -128 to 127 and that raise the error. Also length check was wrong in this case since we have 256 "values" with zero included but maximum length is still 255.

Modifications:

I have fix the validation to allow up to 255 length and changed '>b' range of -128 to 127 to '>B' which mean range of 0 to 255.

Result:

Tag length validation should now correctly support up to 255 characters.