Refactored Container configuration for project types

[alongosz]

Question	Answer
JIRA issue	n/a
Type	improvement
Target Ibexa version	v4.3+
BC breaks	no

This PR moves parts of IbexaExtension configuration related to project configuration (generic and Platform.Sh) to separate strategies, to remove clutter from IbexaExtension class.

TOOD

• more refactoring to reduce cognitive complexity
• tests

Checklist:

• Provided PR description.
• Tested the solution manually.
• Provided automated test coverage.
• Checked that target branch is set correctly (targeting temporarily against Refactored Container configuration for project types #183)
• Ran PHP CS Fixer for new PHP code (use $ composer fix-cs).
• Asked for a review (ping @ibexa/engineering).

[adamwojs]

@alongosz Is this contribution is still relevant ?

[alongosz]

@alongosz Is this contribution is still relevant ?

Yes.