📖 Update PlantUML version (v1.2019.6 -> v1.2022.6)

[oscr]

What this PR does / why we need it:

As requested in another PR. Here is an update of the PlantUML in the CAPI book Dockerfile. I noticed that the newly generated diagrams look a little different so I regenerated all diagrams to ensure a consistent look for all diagrams and to avoid a mix of the old and new style.

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[chrischdi]

/lgtm

I like the new colors 😂

[fabriziopandini]

/lgtm
/approve

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