Regular upgrades of Prestashop

[jchristgit]

Previously, Prestashop upgrades were random and often caused sudden large major version bumps, causing breakage up to data loss.

We should automate regular updates of prestashop as far as possible. A clean solution here might be to pin the version of the Helm chart in some form of requirements file and have renovate or dependabot update it, such that we can then roll it out on our own. A more involved variant would involve either the propose Flux CD deployment #398 or perhaps an alternative like OpenTofu for declaratively managing versions, allowing declarative version bumps.

[jchristgit]

(This somewhat ties into automatic upgrades for a bunch of other things, e.g. Redis could benefit from this as well, but Prestashop is the prime example for how not to do it so far)

[jchristgit]

We will not be moving forward with running Prestashop in the long term, and replacing it with a superior alternative. This is the most I can say at this time.