Build warnings

[Zen0x7]

Hi

I'm using 1.87.0 and my CI is showing the following:

In function 'write_pad2',
    inlined from 'datetime_to_string' at /usr/local/include/boost/mysql/impl/internal/dt_to_string.hpp:125:20,
    inlined from 'append_quoted_datetime' at /usr/local/include/boost/mysql/impl/format_sql.ipp:195:48,
    inlined from 'append_field_view' at /usr/local/include/boost/mysql/impl/format_sql.ipp:254:61:
/usr/local/include/boost/mysql/impl/internal/dt_to_string.hpp:47:18: warning: writing 1 byte into a region of size 0 [-Wstringop-overflow=]
   47 |         *begin++ = '0';
      |                  ^
/usr/local/include/boost/mysql/impl/format_sql.ipp: In function 'append_field_view':
/usr/local/include/boost/mysql/impl/format_sql.ipp:193:10: note: at offset 66 into destination object 'buffer' of size 66
  1[93](https://git.zentrack.cl/zentrack/server/-/jobs/1345#L93) |     char buffer[66];
      |          ^
In function 'write_pad2',
    inlined from 'datetime_to_string' at /usr/local/include/boost/mysql/impl/internal/dt_to_string.hpp:129:20,
    inlined from 'append_quoted_datetime' at /usr/local/include/boost/mysql/impl/format_sql.ipp:1[95](https://git.zentrack.cl/zentrack/server/-/jobs/1345#L95):48,
    inlined from 'append_field_view' at /usr/local/include/boost/mysql/impl/format_sql.ipp:254:61:
/usr/local/include/boost/mysql/impl/internal/dt_to_string.hpp:47:18: warning: writing 1 byte into a region of size 0 [-Wstringop-overflow=]
   47 |         *begin++ = '0';
      |                  ^
/usr/local/include/boost/mysql/impl/format_sql.ipp: In function 'append_field_view':
/usr/local/include/boost/mysql/impl/format_sql.ipp:193:10: note: at offset 66 into destination object 'buffer' of size 66
  193 |     char buffer[66];
      |          ^
In function 'write_pad2',
    inlined from 'time_to_string' at /usr/local/include/boost/mysql/impl/internal/dt_to_string.hpp:174:20,
    inlined from 'append_quoted_time' at /usr/local/include/boost/mysql/impl/format_sql.ipp:213:36,
    inlined from 'append_field_view' at /usr/local/include/boost/mysql/impl/format_sql.ipp:255:53:
/usr/local/include/boost/mysql/impl/internal/dt_to_string.hpp:47:18: warning: writing 1 byte into a region of size 0 [-Wstringop-overflow=]
   47 |         *begin++ = '0';
      |                  ^
/usr/local/include/boost/mysql/impl/format_sql.ipp: In function 'append_field_view':
/usr/local/include/boost/mysql/impl/format_sql.ipp:211:10: note: at offset 66 into destination object 'buffer' of size 66
  211 |     char buffer[66];
      |          ^
In function 'write_pad2',
    inlined from 'time_to_string' at /usr/local/include/boost/mysql/impl/internal/dt_to_string.hpp:178:20,
    inlined from 'append_quoted_time' at /usr/local/include/boost/mysql/impl/format_sql.ipp:213:36,
    inlined from 'append_field_view' at /usr/local/include/boost/mysql/impl/format_sql.ipp:255:53:
/usr/local/include/boost/mysql/impl/internal/dt_to_string.hpp:47:18: warning: writing 1 byte into a region of size 0 [-Wstringop-overflow=]
   47 |         *begin++ = '0';
      |                  ^
/usr/local/include/boost/mysql/impl/format_sql.ipp: In function 'append_field_view':
/usr/local/include/boost/mysql/impl/format_sql.ipp:211:10: note: at offset 66 into destination object 'buffer' of size 66
  211 |     char buffer[66];
      |          ^

I've several hardened flags:

    set(HARDENED_FLAGS
            -Wall -Wextra -Wpedantic -Werror
            -Wshadow -Wnull-dereference -Wdouble-promotion
            -Wconversion -Wsign-conversion -Wold-style-cast
            -Wnon-virtual-dtor -Woverloaded-virtual -Wuseless-cast
            -Wcast-align -Wcast-qual -Wstrict-aliasing=2
            -Waligned-new=all -Wduplicated-cond -Wduplicated-branches
            -Wlogical-op -Wmissing-declarations -Wredundant-decls
            -fsanitize=address,undefined,leak,signed-integer-overflow
            -fno-omit-frame-pointer
            -D_FORTIFY_SOURCE=2
    )

    set(CMAKE_CXX_FLAGS_DEBUG "${CMAKE_CXX_FLAGS_DEBUG} -g --coverage -fsanitize=address,undefined,leak,signed-integer-overflow -fno-omit-frame-pointer")

This is a concern?