Update link_validation.yaml

.github/workflows/link_validation.yaml

@@ -29,7 +29,7 @@ jobs:
           for name in `find . -name "*.md"`; do echo -e "------\n$name" ; mm.py -l $name || exit 1 ;done
       - name: Check Microsoft URLs do not pin localized versions
         run: |
-          localized=$(find . -name '*.md' | xargs grep -ol "\.microsoft\.com/[[:alpha:]]\{2\}-[[:alnum:]]\{2\}/")
+          localized=$(find . -name '*.md' | xargs grep -ol "\.microsoft\.com/[[:alpha:]]\{2\}-[[:alpha:]]\{2\}/")
           if [[ $(echo $localized) ]]; then
             echo "The following files contain links to Microsoft Docs that pin a localized version:"
             echo $localized