docs: fix a grammar issue in multiple files

docs/docs/concepts/scalability_and_resilience.md

@@ -25,7 +25,7 @@ When a graceful shutdown request is received (SIGINT) an instance enters shutdow
 - gives any in-progress runs a limited number of seconds to finish (if not finished it will be put back in the queue)
 - stops the instance from picking up more runs from the queue
 
-If a hard shutdown occurs due to a server crash or an infrastructure failure, any runs that were in progress will be picked up by a internal sweeper task that looks for in-progress runs that have breached their heartbeat window. The sweeper runs every 2 minutes and will put the runs back in the queue for another instance to pick them up.
+If a hard shutdown occurs due to a server crash or an infrastructure failure, any runs that were in progress will be picked up by an internal sweeper task that looks for in-progress runs that have breached their heartbeat window. The sweeper runs every 2 minutes and will put the runs back in the queue for another instance to pick them up.
 
 ## Postgres resilience
 

docs/docs/tutorials/customer-support/customer-support.ipynb

@@ -833,7 +833,7 @@
     "@tool\n",
     "def book_excursion(recommendation_id: int) -> str:\n",
     "    \"\"\"\n",
-    "    Book a excursion by its recommendation ID.\n",
+    "    Book an excursion by its recommendation ID.\n",
     "\n",
     "    Args:\n",
     "        recommendation_id (int): The ID of the trip recommendation to book.\n",

libs/langgraph/langgraph/utils/future.py

@@ -194,7 +194,7 @@ def run_coroutine_threadsafe(
 ) -> asyncio.Future[T]:
     """Submit a coroutine object to a given event loop.
 
-    Return a asyncio.Future to access the result.
+    Return an asyncio.Future to access the result.
     """
 
     if asyncio._get_running_loop() is loop: