Add section on quantum noise to user guide (#2036)

* Add section on q noise to `error-mitigation.md`

Add section on quantum noise to `error-mitigation.md` and clean up wording at end of previous section.

* Clarify lecture notes links are downloads

docs/source/guide/error-mitigation.md

@@ -315,7 +315,15 @@ mitigation:
   (GST) and randomized benchmarking.
 
 This is just a selection of open-source projects related to quantum
-error mitigation. A more comprehensinve collection of software on
-quantum computing can be found
+error mitigation.
+A more comprehensive collection of quantum computing related software can be found
 [here](https://github.com/qosf/awesome-quantum-software) and on [Unitary
 Fund](https://unitary.fund/grants.html)\'s list of supported projects.
+
+### Resources on noise in quantum computers
+
+From the [2023 IBM Qiskit Global Summer School (QGSS23)](https://qiskit.org/events/summer-school-2023):
+- [YouTube lecture (Part 1)](https://www.youtube.com/watch?v=3Ka11boCm1M)
+- Lecture Notes (Part 1): [download from GitHub](https://github.com/qiskit-community/qgss-2023/blob/main/Lecture%20Notes/Lecture%207%20-%20Introduction%20to%20Noise.pdf.zip)
+- Additional Notes Part 1: [download from GitHub](https://github.com/qiskit-community/qgss-2023/blob/main/Lecture%20Notes/Lecture%207%20-%20Bonus%20Content.zip)
+- Lecture notes, lab content, and solutions at the [QGSS23 Hub](https://github.com/qiskit-community/qgss-2023)