aconfig: change Map.of to Map.ofEntries in FakeFeatureFlagsImp

Map.of can only take 10 entries. Map.ofEntries uses variable arguments.

Bug: 303045451
Test: atest AconfigJavaHostTest
Change-Id: I26a3fa0b8a731f9203934d4a800a5c695cfc730f

tools/aconfig/templates/FakeFeatureFlagsImpl.java.template

@@ -37,9 +37,10 @@ public class FakeFeatureFlagsImpl implements FeatureFlags \{
     }
 
     private Map<String, Boolean> mFlagMap = new HashMap<>(
-        Map.of(
+        Map.ofEntries(
             {{-for item in class_elements}}
-            Flags.FLAG_{item.flag_name_constant_suffix}, false{{ if not @last }},{{ endif }}
+            Map.entry(Flags.FLAG_{item.flag_name_constant_suffix}, false)
+            {{ -if not @last }},{{ endif }}
             {{ -endfor }}
         )
     );