Extracted fetching contributors logic to standalone service

[norberttech]

Change Log

Added

• Using Flow cache when reading contributors and fallback to GitHub only when cache expires or does not exists

Fixed

Changed

• Extracted fetching contributors logic to standalone service

Removed

Deprecated

Security

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Description

@stloyd @owsiakl - please follow this convention of not putting logic into controllers.
The same rule applies to stimulus controllers, they should just coordinate services/components, not really hold any logic.

In case of twig, if there is anything repeatable (like classes) use {% set classes = [] %} and then {{ classes|join(' ') }}
For any other twig logic - please extract it to extensions.