Force embedded Guava version

[pdulth]

Guava has many versions.
Capella 7.0 embeds the 31.jre one as it is the latest available for 2023-03.

We need to hardcode the embedded versions in both location:

• In target platform, it allows addons to inherit from it and be able to define a specific version (as we can't have both lazy and fixed one
• In capella feature as if an addon install a prior version of guava in a dropin (e.g. 30), capella startup (reconcile.dropins) will remove guava from the main capella configuration to rely only on the one embedded in the dropin (as both are compatible. when uninstalling the dropin, guava will no longer be found, failling capella to start anymore).