add: .net6 bUnit youtube video plus books and SO (#728)

* add: .net6 bUnit youtube video plus books and SO

* Apply suggestions from code review

Co-authored-by: Egil Hansen <egil@assimilated.dk>

Co-authored-by: Egil Hansen <egil@assimilated.dk>

Author: linkdotnet

docs/site/docs/external-resources.md

@@ -8,6 +8,11 @@ Here is a list of some web content that covers bUnit. If you produce something y
 
 ### Podcasts/Twitch/YouTube/Live coding
 
+- **[Best practices unit testing Blazor components with bUnit](https://www.youtube.com/watch?v=Co7QetPYiO4)**
+  Content is based on 1.3.42 of bUnit.
+- **[What’s new in bUnit for .NET 6](https://www.youtube.com/watch?v=0l88RIyseqE)**
+  Content is based on 1.3.42 of bUnit.
+
 - **[Test Driving the Blazing Pizza Workshop with bUnit (multiple videos)](https://youtube.com/playlist?list=PL2LoDmbC1g20uJjUwPGQxpQjdnmpMqV0t)**  
   Content is based on 1.0.0 of bUnit.
 
@@ -32,3 +37,10 @@ Here is a list of some web content that covers bUnit. If you produce something y
 
 - **[Unit Testing Blazor Components with bUnit and JustMock](https://www.telerik.com/blogs/unit-testing-blazor-components-bunit-justmock) by [Mihail Vladov](https://github.com/mihail-vladov)**  
   Content is based on beta-6 of bUnit.
+
+### Books
+- **[Microsoft Blazor: Building Web Applications in .NET 6 and Beyond](https://www.amazon.com/Microsoft-Blazor-Building-Applications-Beyond/dp/1484278445/ref=sr_1_1?crid=HHEK6NOM4ZLI&amp&keywords=Peter+Himschoot&amp&qid=1641337370&amp&s=books&amp&sprefix=peter+himschoot,stripbooks,79&amp&sr=1-1)**
+- **[Blazor in Action](https://www.manning.com/books/blazor-in-action)**
+
+### Others
+- **[bUnit on Stackoverflow](https://stackoverflow.com/questions/tagged/bunit)**

docs/site/docs/getting-started/index.md

@@ -18,6 +18,12 @@ The *next level* topics are:
 2. **[Verifying output in various ways](xref:verification)** from a component under test, e.g. inspecting the rendered markup.
 3. **[Mocking dependencies](xref:test-doubles)** a component under test has, e.g. the `IJsRuntime` or `HttpClient`.
 
+## Introduction video
+
+This video gives an introduction to bUnit, what it is, why its needed, and how to use it. It covers different testing strategies, and how to build maintainable test and maintainable components.
+
+[![Best practices unit testing Blazor components with bUnit - Egil Hansen - NDC Oslo 2021](https://img.youtube.com/vi/Co7QetPYiO4/0.jpg)](https://www.youtube.com/watch?v=Co7QetPYiO4)
+
 ## Getting help
 
 Can't figure out how to write a test for a testing scenario? Do you have a testing scenario that is hard to write or cannot be written elegantly with bUnit? Have you found a bug in bUnit? Head over to [bUnit’s discussion forum](https://github.com/egil/bUnit/discussions) to ask a question, give feedback, or suggest a new feature. Alternatively, join [bUnits Gitter channel](https://gitter.im/egil/bunit) and let us know. There are no stupid questions - all are welcome!