Make warnings.sh output errs as well

Closes #21532.

tools/warnings.sh

@@ -14,7 +14,8 @@ fi
 
 function show_warnings() {
     echo "${GREEN}Node `basename $1`:${NC}"
-    sed -n 's/^.*\[warn\]//p' $1/info.log | sort | uniq -c | \
+    # Label errs as "Warning:", they're infrequent enough it doesn't matter
+    sed -n -E 's/^.*\[(warn|err)\]//p' $1/info.log | sort | uniq -c | \
     sed -e 's/^\s*//' -e "s/ *\([0-9][0-9]*\) *\(.*\)/ ${YELLOW}Warning:${NC} \2${YELLOW} Number: \1${NC}/"
     echo ""
 }