add back the missing new line at the end of file

Signed-off-by: hai.yue <20416005+yuehaii@users.noreply.github.com>

Author: yuehaii

api/v1alpha1/validation/envoygateway_validate_test.go

@@ -1461,4 +1461,4 @@ func TestLuaDisabled(t *testing.T) {
 			assert.Equal(t, tc.expected, tc.ext.LuaDisabled())
 		})
 	}
-}
+}