Update cppcheck (#5108)

Re-enable cppcheck CI job

Update cppcheck suppression list:
    The new version of cppcheck raises warnings for many potential
    issues that are guarded against, so those warnings have been
    supressed.

Handle realloc failures:
    - jerry-ext/util/sources.c
    - jerry-port/common/jerry-port-io.c

Refactor test-snapshot: move each test to separate functions like some
others already were.

Rename `handler` variables inside `main` of `test-api.c` as they
shadowed the `handler` function in the same file.

JerryScript-DCO-1.0-Signed-off-by: Máté Tokodi mate.tokodi@szteszoftver.hu

tests/unit-core/test-to-integer.c

@@ -110,11 +110,11 @@ main (void)
   TEST_ASSERT (num == ecma_number_make_infinity (false));
 
   /* 5 */
-  ecma_value_t floor = ecma_make_number_value (3.001f);
+  ecma_value_t floor_val = ecma_make_number_value (3.001f);
 
-  result = ecma_op_to_integer (floor, &num);
+  result = ecma_op_to_integer (floor_val, &num);
 
-  ecma_free_value (floor);
+  ecma_free_value (floor_val);
 
   TEST_ASSERT (!ECMA_IS_VALUE_ERROR (result));
   TEST_ASSERT (num == 3);