Fix additional typo

Author: StanFromIreland

.github/workflows/check-for-updates.yml

@@ -25,7 +25,7 @@ jobs:
                       --search 'in:title "Update tzdata to version"' \
                       --json number --jq '.[] | .number')
           if [ -n "$PR_EXISTS" ]; then
-            echo "A PR updating the tzdata version already exists: https://github.com/python/tzdata/pulls/${PR_EXISTS}"
+            echo "A PR updating the tzdata version already exists: https://github.com/python/tzdata/pull/${PR_EXISTS}"
             echo "pr_exists=true" >> "$GITHUB_OUTPUT"
             exit 0
           else