Remove const from testing parameters in testframe framework (#5214)

Makes testing parameters specified with AddTest non-const again when
passed to test functions. This allows test functions to update their
parameters during execution and is particularly useful for tests
which use those parameters to accumulate statistics, error counts,
etc. without resorting to global variables.

c++/test/tarray.cpp

@@ -477,7 +477,7 @@ test_array_info()
  *-------------------------------------------------------------------------
  */
 extern "C" void
-test_array(const void *params)
+test_array(void *params)
 {
     (void)params;