exa: replace stale lock file

[carlocab]

This will hopefully enable bottling for ARM.

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[fxcoudert]

OK for the stale lock file, but don't mess with HEAD (we don't test it regularly, we might forget to move it back, etc)

[carlocab]

@fxcoudert done!

[BrewTestBot]

🤖 A scheduled task has triggered a merge.