.Net & Python: Fix broken links in notebooks (#5698)

### Motivation and Context

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I have fixed broken links found in the `06-memory-and-embeddings.ipynb`
in `notebooks` (both in the `python` and `dotnet`).

### Description

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please see the `Files Changed` tab.

### Contribution Checklist

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- [x] The code builds clean without any errors or warnings
- [x] The PR follows the [SK Contribution
Guidelines](https://github.com/microsoft/semantic-kernel/blob/main/CONTRIBUTING.md)
and the [pre-submission formatting
script](https://github.com/microsoft/semantic-kernel/blob/main/CONTRIBUTING.md#development-scripts)
raises no violations
- [ ] All unit tests pass, and I have added new tests where possible
- [x] I didn't break anyone 😄

Co-authored-by: Mark Wallace <127216156+markwallace-microsoft@users.noreply.github.com>

dotnet/notebooks/06-memory-and-embeddings.ipynb

@@ -203,7 +203,7 @@
    "cell_type": "markdown",
    "metadata": {},
    "source": [
-    "Let's now revisit our chat sample from the [previous notebook](04-context-variables-chat.ipynb).\n",
+    "Let's now revisit our chat sample from the [previous notebook](04-kernel-arguments-chat.ipynb).\n",
     "If you remember, we used kernel arguments to fill the prompt with a `history` that continuously got populated as we chatted with the bot. Let's add also memory to it!"
    ]
   },

python/notebooks/06-memory-and-embeddings.ipynb

@@ -11,10 +11,10 @@
     "So far, we've mostly been treating the kernel as a stateless orchestration engine.\n",
     "We send text into a model API and receive text out.\n",
     "\n",
-    "In a [previous notebook](04-context-variables-chat.ipynb), we used `context variables` to pass in additional\n",
-    "text into prompts to enrich them with more context. This allowed us to create a basic chat experience.\n",
+    "In a [previous notebook](04-kernel-arguments-chat.ipynb), we used `kernel arguments` to pass in additional\n",
+    "text into prompts to enrich them with more data. This allowed us to create a basic chat experience.\n",
     "\n",
-    "However, if you solely relied on context variables, you would quickly realize that eventually your prompt\n",
+    "However, if you solely relied on kernel arguments, you would quickly realize that eventually your prompt\n",
     "would grow so large that you would run into the model's token limit. What we need is a way to persist state\n",
     "and build both short-term and long-term memory to empower even more intelligent applications.\n",
     "\n",