Error for Add testcase to Campain

[qatest]

hi

In version 6.0.0, when we want to add a test case in the campaign, we encounter the following error

What should be done to solve it?

```

[24-01-11 10:30:24.356] SquashTM - 6 WARN [http-nio-8080-exec-9] [ServletWebRequest: uri=/squash/backend/iteration/15/test-plan/resume;client=192.168.10.20;session=05B72EC1D5E8DA59D26E6404D8C55D25;user=ha] --- org.hibernate.engine.jdbc.spi.SqlExceptionHelper: SQL Error: 1054, SQLState: 42S22
[24-01-11 10:30:24.357] SquashTM - 6 ERROR [http-nio-8080-exec-9] [ServletWebRequest: uri=/squash/backend/iteration/15/test-plan/resume;client=192.168.10.20;session=05B72EC1D5E8DA59D26E6404D8C55D25;user=ha] --- org.hibernate.engine.jdbc.spi.SqlExceptionHelper: (conn=29) Unknown column 'explorator3_.ATTACHMENT_LIST_ID' in 'field list'
[24-01-11 10:30:24.359] SquashTM - 6 ERROR [http-nio-8080-exec-9] [ServletWebRequest: uri=/squash/backend/iteration/15/test-plan/resume;client=192.168.10.20;session=05B72EC1D5E8DA59D26E6404D8C55D25;user=ha] --- org.squashtest.tm.web.backend.exceptionresolver.HandlerExceptionLogger: An exception occured while processing request : http://squash.runc.info/squash/backend/ ... lan/resume
org.hibernate.exception.SQLGrammarException: could not extract ResultSet
at org.hibernate.exception.internal.SQLExceptionTypeDelegate.convert(SQLExceptionTypeDelegate.java:63) ~[hibernate-core-5.6.12.Final.jar!/:5.6.12.Final]
at org.hibernate.exception.internal.StandardSQLExceptionConverter.convert(StandardSQLExceptionConverter.java:37) ~[hibernate-core-5.6.12.Final.jar!/:5.6.12.Final]
at org.hibernate.engine.jdbc.spi.SqlExceptionHelper.convert(SqlExceptionHelper.java:113) ~[hibernate-core-5.6.12.Final.jar!/:5.6.12.Final]
at org.hibernate.engine.jdbc.spi.SqlExceptionHelper.convert(SqlExceptionHelper.java:99) ~[hibernate-core-5.6.12.Final.jar!/:5.6.12.Final]
at org.hibernate.engine.jdbc.internal.ResultSetReturnImpl.extract(ResultSetReturnImpl.java:67) ~[hibernate-core-5.6.12.Final.jar!/:5.6.12.Final]
at org.hibernate.loader.plan.exec.internal.AbstractLoadPlanBasedLoader.getResultSet(AbstractLoadPlanBasedLoader.java:390) ~[hibernate-core-5.6.12.Final.jar!/:5.6.12.Final]
at org.hibernate.loader.plan.exec.internal.AbstractLoadPlanBasedLoader.executeQueryStatement(AbstractLoadPlanBasedLoader.java:163) ~[hibernate-core-5.6.12.Final.jar!/:5.6.12.Final]
at org.hibernate.loader.plan.exec.internal.AbstractLoadPlanBasedLoader.executeLoad(AbstractLoadPlanBasedLoader.java:104) ~[hibernate-core-5.6.12.Final.jar!/:5.6.12.Final]
at org.hibernate.loader.collection.plan.AbstractLoadPlanBasedCollectionInitializer.initialize(AbstractLoadPlanBasedCollectionInitializer.java:87) ~[hibernate-core-5.6.12.Final.jar!/:5.6.12.Final]
at org.hibernate.persister.collection.AbstractCollectionPersister.initialize(AbstractCollectionPersister.java:705) ~[hibernate-core-5.6.12.Final.jar!/:5.6.12.Final]
at org.hibernate.event.internal.DefaultInitializeCollectionEventListener.onInitializeCollection(DefaultInitializeCollectionEventListener.java:76) ~[hibernate-core-5.6.12.Final.jar!/:5.6.12.Final]
at org.hibernate.event.service.internal.EventListenerGroupImpl.fireEventOnEachListener(EventListenerGroupImpl.java:107) ~[hibernate-core-5.6.12.Final.jar!/:5.6.12.Final]
at org.hibernate.internal.SessionImpl.initializeCollection(SessionImpl.java:2208) ~[hibernate-core-5.6.12.Final.jar!/:5.6.12.Final]
at org.hibernate.collection.internal.AbstractPersistentCollection$4.doWork(AbstractPersistentCollection.java:595) ~[hibernate-core-5.6.12.Final.jar!/:5.6.12.Final]
at org.hibernate.collection.internal.AbstractPersistentCollection.withTemporarySessionIfNeeded(AbstractPersistentCollection.java:264) ~[hibernate-core-5.6.12.Final.jar!/:5.6.12.Final]
at org.hibernate.collection.internal.AbstractPersistentCollection.initialize(AbstractPersistentCollection.java:591) ~[hibernate-core-5.6.12.Final.jar!/:5.6.12.Final]
at org.hibernate.collection.internal.AbstractPersistentCollection.read(AbstractPersistentCollection.java:149) ~[hibernate-core-5.6.12.Final.jar!/:5.6.12.Final]
at org.hibernate.collection.internal.PersistentList.iterator(PersistentList.java:155) ~[hibernate-core-5.6.12.Final.jar!/:5.6.12.Final]
at java.util.Spliterators$IteratorSpliterator.estimateSize(Unknown Source) ~[?:?]
at java.util.Spliterator.getExactSizeIfKnown(Unknown Source) ~[?:?]
at java.util.stream.AbstractPipeline.copyIntoWithCancel(Unknown Source) ~[?:?]
at java.util.stream.AbstractPipeline.copyInto(Unknown Source) ~[?:?]
at java.util.stream.AbstractPipeline.wrapAndCopyInto(Unknown Source) ~[?:?]
at java.util.stream.MatchOps$MatchOp.evaluateSequential(Unknown Source) ~[?:?]
at java.util.stream.MatchOps$MatchOp.evaluateSequential(Unknown Source) ~[?:?]
at java.util.stream.AbstractPipeline.evaluate(Unknown Source) ~[?:?]
at java.util.stream.ReferencePipeline.anyMatch(Unknown Source) ~[?:?]
at org.squashtest.tm.web.backend.controller.execution.IterationExecutionRunnerController.hasDeletedTestCaseInTestPlan(IterationExecutionRunnerController.java:114) ~[classes!/:?]


```

[plonkarchivist]

Verify that the database schema used by SquashTM matches the expected schema for version 6.0.0.