Fix code scanning alert no. 3: Use of potentially dangerous function

[PythonGermany]

Fixes https://github.com/PythonGermany/42_webserv/security/code-scanning/3

To fix the problem, we need to replace the call to std::gmtime with std::gmtime_r. This change ensures that the tm structure is allocated by the caller, making the function call thread-safe.

• We will modify the getTime function to use std::gmtime_r instead of std::gmtime.
• We will allocate a tm structure on the stack and pass its pointer to std::gmtime_r.
• This change will be made in the file src/utils/utils.cpp at the relevant lines.

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[PythonGermany]

gmtime_r was added in c23