Added Ibexa\Core\FieldType\User\Type::FIELD_TYPE_IDENTIFIER const #1507

Job	Run time
Run code style check (8.0)	2m 41s
Unit tests & SQLite integration tests (7.4)	6m 46s
Solr integration tests (7.4)	9m 33s
Solr integration tests (8.0)	9m 41s
Solr integration tests (8.1)	9m 35s
Unit tests & SQLite integration tests (8.0)	7m 0s
Unit tests & SQLite integration tests (8.1)	6m 50s
MySQL integration tests (7.4)	12m 48s
PostgreSQL integration tests (7.4)	21m 46s
MySQL integration tests (8.0)	12m 37s
PostgreSQL integration tests (8.0)	23m 3s
MySQL integration tests (8.1)	12m 37s
PostgreSQL integration tests (8.1)	28m 19s
	2h 43m 16s

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