[llvm] [libc] Updated GettingStarted.rst with PyYAML version (PR #100649)

[Aiden Grossman via llvm-commits]

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@@ -295,6 +295,7 @@ Package                                                     Version      Notes
 `python <http://www.python.org/>`_                          >=3.8        Automated test suite\ :sup:`1`
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boomanaiden154 wrote:

Side note: This looks like it's different from what is posted at https://github.com/llvm/llvm-project/blob/888ae9066da9c9758c03e839be6cefb3246a9b1c/libc/docs/dev/header_generation.rst?plain=1#L25? Should we just adjust the version on the header generation page to say 3.8 given that is the LLVM project-wide minimum?

https://github.com/llvm/llvm-project/pull/100649