HHH-13704 Make javassist a compile time dependency again

This commit revert some of the changes so that we can release it in a micro
  without breaking application using Javassist.

  In the next minor it should be reverted.

hibernate-core/hibernate-core.gradle

@@ -51,7 +51,8 @@ configurations {
 dependencies {
 
     compile( libraries.jpa )
-    provided( libraries.javassist )
+    // This can now be made provided
+    compile( libraries.javassist )
     // Could be made optional?
     compile( libraries.byteBuddy )
     compile( libraries.antlr )

hibernate-core/src/test/java/org/hibernate/optional/javassist/OptionalJavassistDependencyTest.java

@@ -1,26 +0,0 @@
-/*
- * Hibernate, Relational Persistence for Idiomatic Java
- *
- * License: GNU Lesser General Public License (LGPL), version 2.1 or later
- * See the lgpl.txt file in the root directory or http://www.gnu.org/licenses/lgpl-2.1.html
- */
-package org.hibernate.optional.javassist;
-
-import org.junit.Rule;
-import org.junit.Test;
-import org.junit.rules.ExpectedException;
-
-import static org.junit.Assert.assertNull;
-
-public class OptionalJavassistDependencyTest {
-
-	@Rule
-	public ExpectedException thrown = ExpectedException.none();
-
-	@Test
-	public void shouldNotBeOnTheClasspath() throws Exception {
-		thrown.expect( ClassNotFoundException.class );
-
-		Class<?> aClass = getClass().getClassLoader().loadClass( "javassist.util.proxy.Proxy" );
-	}
-}

hibernate-envers/hibernate-envers.gradle

@@ -11,7 +11,11 @@ apply plugin: 'hibernate-matrix-testing'
 description = 'Hibernate\'s entity version (audit/history) support'
 
 dependencies {
-    compile( project( ':hibernate-core' ) )
+    compile( project( ':hibernate-core' ) ) {
+        // Exclude access to this to avoid future use.
+        exclude group: "org.javassist", module: "javassist"
+    }
+
     provided( libraries.ant )
     annotationProcessor( project( ':hibernate-jpamodelgen' ) )
 

hibernate-osgi/src/test/resources/org/hibernate/osgi/test/testing-bundles.xml

@@ -7,6 +7,5 @@
 <features name="hibernate-osgi-testing-repository" xmlns='http://karaf.apache.org/xmlns/features/v1.2.0'>
     <feature name='hibernate-osgi-testing' version='5.0.0-SNAPSHOT'>
         <bundle>mvn:com.h2database/h2/1.3.170</bundle>
-        <bundle>mvn:org.javassist/javassist/3.24.0-GA</bundle>
     </feature>
 </features>

migration-guide.adoc

@@ -9,11 +9,6 @@ earlier versions, see any other pertinent migration guides as well.
 
 == Known changes
 
-=== Optional Javassist
-
-Javassist is not a transitive dependency of Hibernate ORM core anymore. If you are using it in your
-project you will have to make sure to include it in the classpath of your application.
-
 === Overriding Delayed Identity Insert Behavior
 
 In Hibernate 5.3, we added support for `DelayedPostInsertIdentifier` behavior to be influenced based on the