Remove conditional logic in tests for unsupported JDK versions

JDK 17 is now the minimum supported version.

PiperOrigin-RevId: 705237702

Author: cushon

core/src/test/java/com/google/googlejavaformat/java/FormatterIntegrationTest.java

@@ -48,20 +48,6 @@ public class FormatterIntegrationTest {
 
   private static final ImmutableMultimap<Integer, String> VERSIONED_TESTS =
       ImmutableMultimap.<Integer, String>builder()
-          .putAll(
-              14,
-              "I477",
-              "Records",
-              "RSLs",
-              "Var",
-              "ExpressionSwitch",
-              "I574",
-              "I594",
-              "SwitchComment",
-              "B380299722")
-          .putAll(15, "I603")
-          .putAll(16, "I588", "Sealed")
-          .putAll(17, "I683", "I684", "I696")
           .putAll(
               21,
               "SwitchGuardClause",