Add warning to build scripts if container is older than a day

[deeplow]

Add a heuristic to release build scripts to avoid potentially mistakenly shipping a version with an old container image (never happened but let's make sure it stays that way).

There may be better approaches to this than this simple heuristic but it would already be better than nothing.

[amnak613]

im interested in taking this task on

[almet]

Hey @amnak613 thanks for proposing to help here.

The release scripts are here:

• This is how we build .rpm files (for Fedora): https://github.com/freedomofpress/dangerzone/blob/main/install/linux/build-rpm.py
• This is how we build .deb files (for Debian): https://github.com/freedomofpress/dangerzone/blob/main/install/linux/build-deb.py
• For windows, you might want to add this in the setup-windows.py file, or in https://github.com/freedomofpress/dangerzone/blob/main/install/windows/build-app.bat
• This is how we build .App and .dmg for macOS: https://github.com/freedomofpress/dangerzone/blob/main/install/macos/build-app.py

And if you're interested, you can have a look at the https://github.com/freedomofpress/dangerzone/blob/main/BUILD.md file to get more information about how we build everything.

Just adding a warning to the scripts will be enough, I believe. Because we don't yet have a way to easily share code between the scripts (this is tracked by #946) , the code you add will likely be duplicated between the different scripts.

Don't hesitate if you have any further question!