MINOR: h3: check return values of htx_add_* on headers parsing

Check return values of htx_add_header()/htx_add_eof() during H3 HEADERS
conversion to HTX. In case of error, the connection is interrupted with
a CONNECTION_CLOSE.

This commit is useful to detect abnormal situation on headers parsing.
It should be backported up to 2.7.
1 file changed