docs: minor formatting change for how to docs

docs/docs/how-tos/persistence_mongodb.ipynb

@@ -37,10 +37,10 @@
     "    </p>\n",
     "</div>\n",
     "\n",
-    "For demonstration purposes we add persistence to the [pre-built create react agent](https://langchain-ai.github.io/langgraph/reference/prebuilt/#langgraph.prebuilt.chat_agent_executor.create_react_agent), but you can add a checkpointer to any custom graph that you build.\n",
+    "For demonstration purposes we add persistence to the [pre-built create react agent](https://langchain-ai.github.io/langgraph/reference/prebuilt/#langgraph.prebuilt.chat_agent_executor.create_react_agent).\n",
+    "\n",
+    "In general, you can add a checkpointer to any custom graph that you build like this:\n",
     "\n",
-    "## TLDR\n",
-    " \n",
     "```python\n",
     "from langgraph.graph import StateGraph\n",
     "\n",

docs/docs/how-tos/persistence_postgres.ipynb

@@ -30,7 +30,9 @@
     "\n",
     "This how-to guide shows how to use `Postgres` as the backend for persisting checkpoint state using the [`langgraph-checkpoint-postgres`](https://github.com/langchain-ai/langgraph/tree/main/libs/checkpoint-postgres) library.\n",
     "\n",
-    "For demonstration purposes we add persistence to the [pre-built create react agent](https://langchain-ai.github.io/langgraph/reference/prebuilt/#langgraph.prebuilt.chat_agent_executor.create_react_agent), but you can add a checkpointer to any custom graph that you build.\n",
+    "For demonstration purposes we add persistence to the [pre-built create react agent](https://langchain-ai.github.io/langgraph/reference/prebuilt/#langgraph.prebuilt.chat_agent_executor.create_react_agent). \n",
+    "\n",
+    "In general, you can add a checkpointer to any custom graph that you build like this:\n",
     "\n",
     "```python\n",
     "from langgraph.graph import StateGraph\n",

docs/docs/how-tos/persistence_redis.ipynb

@@ -37,8 +37,9 @@
     "    </p>\n",
     "</div>\n",
     "\n",
-    "For demonstration purposes we add persistence to the [pre-built create react agent](https://langchain-ai.github.io/langgraph/reference/prebuilt/#langgraph.prebuilt.chat_agent_executor.create_react_agent), but you can add a checkpointer to any custom graph that you build.\n",
+    "For demonstration purposes we add persistence to the [pre-built create react agent](https://langchain-ai.github.io/langgraph/reference/prebuilt/#langgraph.prebuilt.chat_agent_executor.create_react_agent).\n",
     "\n",
+    "In general, you can add a checkpointer to any custom graph that you build like this:\n",
     "\n",
     "```python\n",
     "from langgraph.graph import StateGraph\n",