* rewrite `just update` command to provide a one-line command to update everything
* update prefix
* uncomment update-self
* Revert requirements.yml updates not belonging to this PR
* Justfile and documentation updates to make things clearer
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Co-authored-by: Slavi Pantaleev <slavi@devture.com>
It should be noted that this cannot be used for the initial install
of services which require a database or have other dependencies.
Those would typically need to invoke the playbook with
`--tags=install-postgres,install-SERVICE`, etc.
The purpose of this shortcut is to easily rebuild and restart
a single serice subsequently. For those cases, often times there's no need to
reinitialize the database and other components and simply running a
single component's tasks is enough.