Revert "stat command changed (eth-educators#1750)"

This reverts commit 3d3a6d0.

ethd

@@ -3502,7 +3502,13 @@ fi
 
 cd "$(dirname "$(realpath "${BASH_SOURCE[0]}")")"
 # Use this to make sure root doesn't end up owning files
-OWNER=$(stat --format=%U .)
+if [[ "$OSTYPE" == "darwin"* ]]; then
+# This is a macOS-ism
+# shellcheck disable=SC2016
+  OWNER=$(stat -f '$Su' .)
+else
+  OWNER=$(stat -c '%U' .)
+fi
 
 if [ "${OWNER}" == "root" ]; then
   echo "Please install Eth Docker as a non-root user."