feat: Certify Charts and Dashboards (#17335)

* Certify charts

* Format

* Certify dashboards

* Format

* Refactor card certification

* Clear details when certified by empty

* Show certification in detail page

* Add RTL tests

* Test charts api

* Enhance integration tests

* Lint

* Fix dashboards count

* Format

* Handle empty value

* Handle empty slice

* Downgrade migration

* Indent

* Use alter

* Fix revision

* Fix revision

superset/models/slice.py

@@ -81,6 +81,8 @@ class Slice(  # pylint: disable=too-many-public-methods
     # when the database row was last written
     last_saved_at = Column(DateTime, nullable=True)
     last_saved_by_fk = Column(Integer, ForeignKey("ab_user.id"), nullable=True)
+    certified_by = Column(Text)
+    certification_details = Column(Text)
     last_saved_by = relationship(
         security_manager.user_model, foreign_keys=[last_saved_by_fk]
     )
@@ -211,6 +213,8 @@ class Slice(  # pylint: disable=too-many-public-methods
             "slice_id": self.id,
             "slice_name": self.slice_name,
             "slice_url": self.slice_url,
+            "certified_by": self.certified_by,
+            "certification_details": self.certification_details,
         }
 
     @property