CI: Fix typo in comment

.github/workflows/linux-old.yml

@@ -9,7 +9,7 @@
 # Debian stretch is chosen as it closely matches some of the oldest major
 # versions we support (especially cmake); see docs/INTERNALS.md and it
 # is still supported (as of this writing).
-# stretch has ELTS support from Feexian until 2027-06-30
+# stretch has ELTS support from Freexian until 2027-06-30
 # For ELTS info see https://www.freexian.com/lts/extended/docs/how-to-use-extended-lts/
 # The Debian key will expire 2025-05-20, after which package signature
 # verification may need to be disabled.