DBI versions before 1.650 for Perl read one byte out-of-bounds in preparse when deleting an initial SQL comment

DBI versions before 1.650 for Perl read one byte out-of-bounds in preparse when deleting an initial SQL comment.

The preparse method normalises SQL and removes comments. When the SQL starts with a comment line, the deletion of that line during normalisation led to an out-of-bounds read by one byte. The result is a fault on memory-hardened builds and nondeterministic newline retention on normal builds.