Make Testing Sling Mock Oak compatible with Java14+, Update to Oak 1.40.0

java.lang.NoClassDefFoundError: java/security/acl/Group
	at org.apache.jackrabbit.oak.security.user.UserConfigurationImpl.getUserPrincipalProvider(UserConfigurationImpl.java:245)
	at org.apache.jackrabbit.oak.security.principal.PrincipalConfigurationImpl.getPrincipalProvider(PrincipalConfigurationImpl.java:75)
	at org.apache.jackrabbit.oak.spi.security.principal.CompositePrincipalConfiguration.getPrincipalProvider(CompositePrincipalConfiguration.java:55)
	at org.apache.jackrabbit.oak.spi.security.authentication.AbstractLoginModule.getPrincipalProvider(AbstractLoginModule.java:454)
	at org.apache.jackrabbit.oak.spi.security.authentication.AbstractLoginModule.getPrincipals(AbstractLoginModule.java:490)
	at org.apache.jackrabbit.oak.security.authentication.user.LoginModuleImpl.commit(LoginModuleImpl.java:167)
	at java.base/javax.security.auth.login.LoginContext.invoke(LoginContext.java:737)
	at java.base/javax.security.auth.login.LoginContext$4.run(LoginContext.java:672)
	at java.base/javax.security.auth.login.LoginContext$4.run(LoginContext.java:670)
	at java.base/java.security.AccessController.doPrivileged(AccessController.java:712)
	at java.base/javax.security.auth.login.LoginContext.invokePriv(LoginContext.java:670)
	at java.base/javax.security.auth.login.LoginContext.login(LoginContext.java:581)
	at org.apache.jackrabbit.oak.core.ContentRepositoryImpl.login(ContentRepositoryImpl.java:163)
	at org.apache.jackrabbit.oak.jcr.repository.RepositoryImpl.login(RepositoryImpl.java:288)
	at org.apache.jackrabbit.oak.jcr.repository.RepositoryImpl.login(RepositoryImpl.java:226)
	at org.apache.sling.testing.mock.sling.oak.OakMockSlingRepository.login(OakMockSlingRepository.java:123)
	at org.apache.sling.testing.mock.sling.oak.OakMockSlingRepository.loginAdministrative(OakMockSlingRepository.java:139)
	at org.apache.sling.testing.mock.sling.ResourceResolverFactoryInitializer.registerJcrNodeTypes(ResourceResolverFactoryInitializer.java:235)
	at org.apache.sling.testing.mock.sling.ResourceResolverFactoryInitializer.setUp(ResourceResolverFactoryInitializer.java:69)
	at org.apache.sling.testing.mock.sling.MockSling.newResourceResolverFactory(MockSling.java:87)
	at ...
Caused by: java.lang.ClassNotFoundException: java.security.acl.Group
	at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:641)
	at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:188)
	at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:520)
	... 49 more