add a few new warnings to the 10.0 clang release notes

- ``-Wbitwise-op-parentheses`` and ``-Wlogical-op-parentheses`` are disabled by default.

- The new warnings ``Wc99-designator`` and ``-Wreorder-init-list`` warn about

  uses of C99 initializers in C++ mode for cases that are valid in C99 but not

  in C++20.

- The new warning ``-Wsizeof-array-div`` catches cases like

  ``int arr[10]; ...sizeof(arr) / sizeof(short)...``

  (should be ``sizeof(arr) / sizeof(int)``), and the existing warning

  ``-Wsizeof-pointer-div`` catches more cases.

- The new warning ``-Wxor-used-as-pow`` warns on cases where it looks like

  the xor operator ``^`` is used to be mean exponentiation, e.g. ``2 ^ 16``.

- The new warning ``-Wfinal-dtor-non-final-class`` warns on classes that

  have a final destructor but aren't themselves marked final.

- ``-Wextra`` now enables ``-Wdeprecated-copy``. The warning deprecates

  move and copy constructors in classes where an explicit destructor is

  declared. This is for compatibility with GCC 9, and forward looking

  for a change that's being considered for C++23. You can disable it with

  ``-Wno-deprecated-copy``.

Non-comprehensive list of changes in this release

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