Fix Cygwin CI after #32841 (#35052)

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### 📚 Description

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Cygwin workflows were mangled by a bad merge, leading to syntax errors
even whenever the workflow is parsed.

Here we fix this; note that the Cygwin workflow is still not functional
afterward (the first step, installation of Cygwin with choco, fails).
But this will only affect builds of releases and does not happen for PR
CI runs.
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Closes #35048 

### 📝 Checklist

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### ⌛ Dependencies
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