wrap Expected value macro bodies in parentheses

[sophiapoirier]

The Expected value macros AUSDK_UnwrapOrReturnError, AUSDK_UnwrapOrReturnVoid, and AUSDK_UnwrapOrReturnUnexpected aren't well encapsulated with parentheses around their bodies, making them unusable in expressions dereferencing the value results, e.g.:

AUSDK_UnwrapOrReturnError(GetOutput0().GetBufferListOrError()).mNumberBuffers;

reduced error messages:

error: no member named 'mNumberBuffers' in 'ausdk::ExpectedPtr<AudioBufferList>'; did you mean to use '->' instead of '.'?
 1656 |         AUSDK_UnwrapOrReturnError(theOutput.GetBufferListOrError()).mNumberBuffers;
      |                                                                                                  ^
      |                                                                                                  ->
error: indirection requires pointer operand ('UInt32' (aka 'unsigned int') invalid)
 1656 |         AUSDK_UnwrapOrReturnError(theOutput.GetBufferListOrError()).mNumberBuffers;
      |                                       ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
AudioUnitSDK/include/AudioUnitSDK/AUUtility.h:80:2: note: expanded from macro 'AUSDK_UnwrapOrReturnError'
   80 |         *({                                                                                           \
      |         ^

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