Remove deprecated code.

This removes most currently deprecated code.

An exception are various deprecations in Spring Data R2DBC for which it is not obvious how to modify the code that is still using the deprecated API.

Original pull request #1304

spring-data-jdbc/src/test/java/org/springframework/data/jdbc/mapping/model/NamingStrategyUnitTests.java

@@ -77,12 +77,6 @@ public class NamingStrategyUnitTests {
 		assertThat(target.getSchema()).isEqualTo("");
 	}
 
-	@Test // DATAJDBC-184
-	public void getQualifiedTableName() {
-
-		assertThat(target.getQualifiedTableName(persistentEntity.getType())).isEqualTo("dummy_entity");
-	}
-
 	@Data
 	private static class DummyEntity {