Disable gate dispatcher on x64 MacOS

[mlxd]

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---

Context: Due to intermittent failures on the CI, this PR disable the dynamic dispatcher on x64 MacOS builds of LightningQubit.

Description of the Change: As above.

Benefits: Ensures successful builds of the packages for testing and validation across ecosystem.

Possible Drawbacks:

Related GitHub Issues:

[mlxd]

[sc-61797]

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 98.67%. Comparing base (43f7a91) to head (cc122b2).

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #697      +/-   ##
==========================================
+ Coverage   98.58%   98.67%   +0.09%     
==========================================
  Files         174      174              
  Lines       22629    22629              
==========================================
+ Hits        22309    22330      +21     
+ Misses        320      299      -21     

☔ View full report in Codecov by Sentry.
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[vincentmr]

LGTM too! But isn't this change going to disable the dispatcher on all MacOS platforms (not just x64)?

[mlxd]

LGTM too! But isn't this change going to disable the dispatcher on all MacOS platforms (not just x64)?

There's no dispatcher support on anything but x64, so it won't affect the ARM builds in any way, so I think it's fine. If we intend to add ARM intrinsics later, we'll need to restructure the dispatcher anyway, so that's probably the best time to re-evaluate.

[vincentmr]

LGTM too! But isn't this change going to disable the dispatcher on all MacOS platforms (not just x64)?

There's no dispatcher support on anything but x64, so it won't affect the ARM builds in any way, so I think it's fine. If we intend to add ARM intrinsics later, we'll need to restructure the dispatcher anyway, so that's probably the best time to re-evaluate.

Ah, yes, of course. All good then.

[mlxd]

Thanks @vincentmr and @jay-selby