fix: replace ibexa/admin-ui-assets with se7enxweb/admin-ui-assets (v5 pure)

se7enxweb/admin-ui-assets is the fork that installs to vendor/se7enxweb/
and sets the @ibexa-admin-ui-assets webpack alias correctly.
ibexa/admin-ui-assets dev-5.0-next installs to vendor/ibexa/ which breaks
all encore configs in se7enxweb/admin-ui that hardcode vendor/se7enxweb/admin-ui-assets.

Author: se7enxweb

composer.json

@@ -11,7 +11,7 @@
         "ibexa/doctrine-schema": "~5.0.x-dev",
         "se7enxweb/system-info": "~5.0.x-dev",
         "se7enxweb/admin-ui": "^5.0.5.0",
-        "ibexa/admin-ui-assets": "dev-5.0-next",
+        "se7enxweb/admin-ui-assets": "5.0.0.x-dev",
         "ibexa/content-forms": "~5.0.x-dev",
         "se7enxweb/exponential-platform-dxp-core": "^5.0.1.0",
         "ibexa/core-persistence": "~5.0.x-dev",