update pre commit

Author: rambasnet

.githooks/pre-commit

@@ -5,7 +5,7 @@ LC_ALL=C
 current_branch=$(git rev-parse --abbrev-ref HEAD)
 echo "Running pre-commit hook on branch: $current_branch"
 if [[ "$current_branch" == "main" ]]; then
-    echo "Commit on main is now allowed. Please use a feature branch."
+    echo "Commit on main is not allowed. Please use a feature branch."
     exit 1
 fi
 

notebooks/CommonDesignPatterns.ipynb

@@ -1452,7 +1452,7 @@
    "source": [
     "class OneOnly:\n",
     "    _singleton = None\n",
-    "    # not the use of cls instead of cls to clarify the usage of _sigleton class variable\n",
+    "    # not the use of cls instead of self to clarify the usage of _sigleton class variable\n",
     "    def __new__(cls, *args, **kwargs):\n",
     "        if not cls._singleton:\n",
     "            cls._singleton = super().__new__(cls, *args, **kwargs)\n",