Adapt to change in Gerrit core

In Ia177bc8cfd6 InternalGroup was moved to the entities package.

Change-Id: If66f3a1534a750bece27340e192a09cc11a237e9

src/main/java/com/googlesource/gerrit/plugins/saml/SamlMembership.java

diff --git a/src/main/java/com/googlesource/gerrit/plugins/saml/SamlMembership.java b/src/main/java/com/googlesource/gerrit/plugins/saml/SamlMembership.java
index e1ba2c0..06940dc 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/saml/SamlMembership.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/saml/SamlMembership.java
@@ -19,11 +19,11 @@
 import com.google.common.collect.Sets;
 import com.google.gerrit.entities.Account;
 import com.google.gerrit.entities.AccountGroup;
+import com.google.gerrit.entities.InternalGroup;
 import com.google.gerrit.server.GerritPersonIdent;
 import com.google.gerrit.server.IdentifiedUser;
 import com.google.gerrit.server.ServerInitiated;
 import com.google.gerrit.server.account.*;
-import com.google.gerrit.server.group.InternalGroup;
 import com.google.gerrit.server.group.db.GroupsUpdate;
 import com.google.gerrit.server.group.db.InternalGroupCreation;
 import com.google.gerrit.server.group.db.InternalGroupUpdate;