Update clang-format requirements in documentation (#1048)

* Clean up api sample base class interfaces

* Revert "Clean up api sample base class interfaces"

This reverts commit 7504395.

* Update clang-format documentation
Use consistent wording and version requirement

CONTRIBUTING.adoc

@@ -145,7 +145,7 @@ A common code style like, for instance, the one described by the https://google.
 A sample must consistently apply a single code style.
 
 A `.clang-format` file is included with this repository, please use `clang-format -style=file` to verify the code style.
-Ensure that you are using clang-format 8.
+It is recommended to use `clang-format-15`, which is compatible with the styles in our `.clang-format` file.
 
 == Procedure for Contributing
 

docs/build.adoc

@@ -149,7 +149,6 @@ ____
 
 It is recommended to use `clang-format-15`, which is compatible with the styles in our `.clang-format` file.
 It is also used by CI and is a basic version installed with Visual Studio 2022.
-The minimum version that supports our current `.clang-format` file is `clang-format-9`.
 
 Go to the http://releases.llvm.org/download.html[LLVM downloads page] to get clang.