Compile time in image header not updated by build

[pg_esp32]

When I change a source file and then execute "idf.py build" (on Windows), the required files will be compiled and a new *.bin file for the application is created. However the compile time/date in the image header of the build file is not updated (time of first build probably).
How can this be fixed? (with minimal slow-down of the build duration)

I'm currently using IDF 5.3.1 but the behavior in older versions is the same.
Changing version.txt slows down the build but still does not update the compile time.
A fix to include in the CMakeLists.txt files would be preferred so a simple "idf.py build" is still enough, no additional commands needed.