Fix typo (#5361)

Just fix typo

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Author: weijen

python/packages/autogen-core/docs/src/user-guide/agentchat-user-guide/tutorial/termination.ipynb

@@ -10,7 +10,7 @@
                 "\n",
                 "AgentChat supports several termination condition by providing a base {py:class}`~autogen_agentchat.base.TerminationCondition` class and several implementations that inherit from it.\n",
                 "\n",
-                "A termination condition is a callable that takes a sequece of {py:class}`~autogen_agentchat.messages.AgentEvent` or {py:class}`~autogen_agentchat.messages.ChatMessage` objects **since the last time the condition was called**, and returns a {py:class}`~autogen_agentchat.messages.StopMessage` if the conversation should be terminated, or `None` otherwise.\n",
+                "A termination condition is a callable that takes a sequence of {py:class}`~autogen_agentchat.messages.AgentEvent` or {py:class}`~autogen_agentchat.messages.ChatMessage` objects **since the last time the condition was called**, and returns a {py:class}`~autogen_agentchat.messages.StopMessage` if the conversation should be terminated, or `None` otherwise.\n",
                 "Once a termination condition has been reached, it must be reset by calling {py:meth}`~autogen_agentchat.base.TerminationCondition.reset` before it can be used again.\n",
                 "\n",
                 "Some important things to note about termination conditions: \n",