HTTP/3: fix QPACK static table values to match RFC 9204

HTTP/3: fix QPACK static table values to match RFC 9204

Five values of the static table lacked the space after a semicolon
compared to RFC 9204, Appendix A: indexes 52, 57, 58, 62 and 85.  A
field sent by a client as an indexed static entry was thus decoded
without the space, for example "text/html;charset=utf-8" instead of
"text/html; charset=utf-8" in the Content-Type header.  The encoder
is not affected, it does not use these indexes.