fix: remove unused variable test=develop

lite/tests/kernels/pow_compute_test.cc

@@ -65,16 +65,12 @@ class PowComputeTester : public arena::TestCase {
 };
 
 void test_pow(Place place) {
-  for (float scale : {0.923, 2., 1.2}) {
-    for (float shift : {1., 0., 1.2331}) {
   for (float factor : {1., 1.2, 1.6}) {
     std::unique_ptr<arena::TestCase> tester(
         new PowComputeTester(place, "def", factor));
     arena::Arena arena(std::move(tester), place, 2e-4);
     arena.TestPrecision();
   }
-    }
-  }
 }
 
 TEST(Pow, precision) {