[clang] [clang][docs] Improve "Obtaining Clang" section (PR #71313)

[Robin Caloudis via cfe-commits]

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@@ -22,8 +22,8 @@ started guide <https://llvm.org/docs/GettingStarted.html>`_.
 
 .. code-block:: console
 
-      cd ~/clang-llvm
-      git clone https://github.com/llvm/llvm-project.git
+      mkdir ~/clang-llvm && cd ~/clang-llvm
+      git clone https://github.com/llvm/llvm-project.git .
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robincaloudis wrote:

Thanks for the review @jrtc27. Indeed, having the `llvm-project` subdirectory is much cleaner. I updated all required steps. Found some more outdated details. Please re-review. Thank you.

https://github.com/llvm/llvm-project/pull/71313