Add traits-annotations to StandardEntity

[Rumata42]

StandardEntity has fields deletedBy, deletedAs, etc, and corresponding interfaces to mark traits, but Jmix uses annotations for that goal. So these fields should be annotated as @DeletedBy, @DeletedDate, etc.

QA Notes:
Use project migrated from CUBA
Check that SoftDelete and other traits are displayed on entity screen in studio for entities inherited from com.haulmont.cuba.core.entity.StandardEntity

[maistrenkoIulia]

Jmix version: 1.2.0-SNAPSHOT
Jmix Studio plugin version: 1.1.SNAPSHOT3632-212
IntelliJ version: IntelliJ IDEA 2021.2.2 (Ultimate Edition)

[dtaimanov]

@maistrenkoIulia, wrong entity used: Parent field is empty, but should be StandardEntity [sys$StandardEntity]

[maistrenkoIulia]

verified