gh-39427: Remove deprecated sage-cython script
    
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It's deprectaed since v8.7 and is no longer in use in sage, so should be
safe to be deleted.

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URL: #39427
Reported by: Tobias Diez
Reviewer(s):

Author: Release Manager

src/bin/sage-cython

@@ -57,8 +57,6 @@ scripts =
     bin/sage-runtests
     bin/sage-fixdoctests
     bin/sage-coverage
-    # The following is deprecated but might still be used in user package install scripts
-    bin/sage-cython
     # Helper scripts invoked by sage script
     # (they would actually belong to something like libexec)
     bin/sage-cachegrind