Set correct language version for str.data() to be non-const char*

tests/deps/use-cryptopp/gcc.tc.jsonc

 {
     "compiler_id": "gnu",
     "cxx_compiler": "g++-9",
+    "cxx_version": "c++17",
     // All required for Crypto++ intrinsics:
-    "flags": "-msse2 -msse3 -mssse3 -msse4.1 -msse4.2 -mpclmul -maes -mavx -mavx2 -msha",
+    "flags": "-msse2 -msse3 -mssse3 -msse4.1 -msse4.2 -mpclmul -maes -mavx -mavx2 -msha -Wa,-q",
 }

tests/deps/use-cryptopp/msvc.tc.jsonc

 {
     "compiler_id": 'msvc',
+    "flags": "/std:c++17"
 }