Compile error for using qtl::bind_field with 'std::vector<char>'

[Nickllsn]

/usr/include/c++/9/bits/stl_vector.h:746:7: note: conversion of argument 1 would be ill-formed:
In file included from ../../thirdparty/qtl/include/qtl_sqlite.hpp:8,
......
../../thirdparty/qtl/include/qtl_common.hpp:86:63: error: invalid conversion from ‘const char_type*’ {aka ‘const char*’} to ‘std::vector::size_type’ {aka ‘long unsigned int’} [-fpermissive]
86 | void assign(const char_type* str, size_t n) { m_value.assign(str, n); }
| ^~~
| |
| const char_type* {aka const char*}