Python: Run notebooks as tests (microsoft#6430)

### Motivation and Context

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Run notebooks as tests, working for all gettings started notebooks.
Also updated learn resources samples test, this can now easily be
extended with other sample scripts.

Closes: microsoft#4637
Partially closes: microsoft#4638

### Description

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### 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
- [x] All unit tests pass, and I have added new tests where possible
- [x] I didn't break anyone 😄

python/pyproject.toml

@@ -60,6 +60,7 @@ pyarrow = { version = ">=12.0.1,<16.0.0", optional = true}
 pre-commit = ">=3.7.1"
 ruff = ">=0.4.5"
 ipykernel = "^6.29.4"
+nbconvert = "^7.16.4"
 pytest = "^8.2.1"
 pytest-asyncio = "^0.23.7"
 snoop = "^0.4.3"

python/samples/getting_started/00-getting-started.ipynb

@@ -146,7 +146,10 @@
     "\n",
     "joke_function = plugin[\"Joke\"]\n",
     "\n",
-    "joke = await kernel.invoke(joke_function, KernelArguments(input=\"time travel to dinosaur age\", style=\"super silly\"))\n",
+    "joke = await kernel.invoke(\n",
+    "    joke_function,\n",
+    "    KernelArguments(input=\"time travel to dinosaur age\", style=\"super silly\"),\n",
+    ")\n",
     "print(joke)"
    ]
   }