[llvm] [docs] Add beginner-focused office hours (PR #80308)

[Natalie Chouinard via llvm-commits]

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@@ -331,6 +331,11 @@ don't find anyone present, chances are they happen to be off that day.
     - Monthly, 4th Wednesday of the month at 9:30am PT, for 30 minutes.
     - `Google meet <https://meet.google.com/pdd-dibg-cwv>`__
     - English
+  * - Rotating hosts
+    - Getting Started, beginner questions, new contributors.
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sudonatalie wrote:

I was actually hoping that intentionally vague could be a feature not a bug! For the newest contributors that might not know which of the above office hours or working groups would help them, I hope this might be a place we can answer very beginner questions or direct them towards the other available resources that are more specific to their issue.

https://github.com/llvm/llvm-project/pull/80308