IBX-2961: Implemented ConfigurationDumper for Ibexa Encore files

[alongosz]

Question	Answer
JIRA issue	IBX-2961
Required by	IBX-2961: Fixed extensibility point for adding plugins in CKEditor fieldtype-richtext#46 IBX-2961: Refactored Extension to rely on Encore Configuration Dumper admin-ui#471
Type	feature
Target Ibexa version	v4.1+
BC breaks	no

Based on fb9c26f.

This PR provides the new ConfigurationDumper class to be used by 1st party Ibexa packages to provide Ibexa Encore extension points, like the one in ibexa/fieldtype-richtext#46.

The differences with fb9c26f are that the code was encapsulated into a class, so 1st party usage is as simple as possible. Moreover it's project-first, following philosophy of Symfony which got rid of AppBundle and extracted Resources to top-level project directories. It's possible to place required file either in top level encore/ directory or bundle-level Resources/encore directory.

Why in ibexa/core?

We need to provide an extension point in ibexa/fieldtype-richtext which has no knowledge of AdminUI. At the same time the mechanism used there will be common for the future extension points, so ibexa/core ATM makes the most sense (as core was meant to be a merge of former ezplatform-core and ezplatform-kernel).

Checklist:

• Provided PR description.
• Tested the solution manually.
• Provided automated test coverage.
• Checked that target branch is set correctly (main for features, the oldest supported for bugs).
• Ran PHP CS Fixer for new PHP code (use $ composer fix-cs).
• Asked for a review.

[alongosz]

@adamwojs fixed all remarks via fe690df... and via f1ca6ee (my bad).

[mikadamczyk]

you could introduce variable/property for $this->projectDir . self::FOO_BAR_BUNDLE_DIR e.g $this->fooBarBundlePath

[alongosz]

you could introduce variable/property for $this->projectDir . self::FOO_BAR_BUNDLE_DIR e.g $this->fooBarBundlePath

Fixed via c7d892c