Formatters in parseDateTime and formatDateTime Now Support Hours/Months Without Leading Zeros

Formatters %l/%k/%c in function parseDateTime are now able to parse hours/months without leading zeros, e.g. select parseDateTime('2023-11-26 8:14', '%F %k:%i') now works. Set parsedatetime_parse_without_leading_zeros = 0 to restore the previous behavior which required two digits. Function formatDateTime is now also able to print hours/months without leading zeros. This is controlled by setting formatdatetime_format_without_leading_zeros but off by default to not break existing use cases. #55872 (Azat Khuzhin).