docs: update some bug tracker references (NFC)

[keith]

Summary

Fixes https://github.com/llvm/llvm-project/issues/53091

[keith]

Kick CI

[keith]

There are quite a few more, but I'm just trying to quickly fix up some of the ones folks noticed. Also note I updated the wording a bit since the workflow is slightly different for folks without push access to the repo. In that case they cannot add labels nor assign themselves to issues AFAIK

[asl]

llvm/docs/Contributing.rst

28–29

Should it be just beginner_ keyword?

[keith]

Update link

[asl]

LGTM, thanks!

CONTRIBUTING.md

 # Contributing to LLVM
 
 Thank you for your interest in contributing to LLVM! There are many ways to
 contribute, and we appreciate all contributions.
 
 To get started with contributing, please take a look at the
 [Contributing to LLVM](https://llvm.org/docs/Contributing.html) guide. It
 describes how to get involved, raise issues and submit patches. Please note
-that at the moment the LLVM project does not use either Github pull requests
-or Github issues.
+that at the moment the LLVM project does not use GitHub pull requests.

llvm/docs/Contributing.rst

 Bug Reports
 -----------
 If you are working with LLVM and run into a bug, we definitely want to know
 about it. Please let us know and follow the instructions in
 :doc:`HowToSubmitABug`  to create a bug report.
 
 Bug Fixes
 ---------
 If you are interested in contributing code to LLVM, bugs labeled with the
-`beginner keyword`_ in the `bug tracker`_ are a good way to get familiar with
-the code base. If you are interested in fixing a bug, please create an account
-for the bug tracker and assign it to yourself, to let people know you are working on
-it.
+`beginner`_ keyword in the `bug tracker`_ are a good way to get familiar with
+the code base. If you are interested in fixing a bug please comment on it to
+let people know you are working on it.
 
 Then try to reproduce and fix the bug with upstream LLVM. Start by building
 LLVM from source as described in :doc:`GettingStarted` and
 and use the built binaries to reproduce the failure described in the bug. Use
 a debug build (`-DCMAKE_BUILD_TYPE=Debug`) or a build with assertions
 (`-DLLVM_ENABLE_ASSERTIONS=On`, enabled for Debug builds).
 
 Reporting a Security Issue

 
 `Intro to LLVM`__
   Book chapter providing a compiler hacker's introduction to LLVM.
 
   .. __: http://www.aosabook.org/en/llvm.html
 
 .. _Developer's List (llvm-dev): http://lists.llvm.org/mailman/listinfo/llvm-dev
 .. _irc.oftc.net: irc://irc.oftc.net/llvm
-.. _beginner keyword: https://bugs.llvm.org/buglist.cgi?bug_status=NEW&bug_status=REOPENED&keywords=beginner%2C%20&keywords_type=allwords&list_id=130748&query_format=advanced&resolution=---
-.. _bug tracker: https://bugs.llvm.org
+.. _beginner: https://github.com/llvm/llvm-project/issues?q=is%3Aopen+is%3Aissue+label%3Abeginner
+.. _bug tracker: https://github.com/llvm/llvm-project/issues
 .. _clang-format-diff.py: https://reviews.llvm.org/source/llvm-github/browse/main/clang/tools/clang-format/clang-format-diff.py
 .. _git-clang-format: https://reviews.llvm.org/source/llvm-github/browse/main/clang/tools/clang-format/git-clang-format
 .. _LLVM's Phabricator: https://reviews.llvm.org/
 .. _LLVM's Open Projects page: https://llvm.org/OpenProjects.html#what
 .. _LLVM Developer's mailing list: http://lists.llvm.org/mailman/listinfo/llvm-dev

llvm/docs/HowToSubmitABug.rst

 Basically you have to do two things at a minimum. First, decide whether the
 bug `crashes the compiler`_ or if the compiler is `miscompiling`_ the program
 (i.e., the compiler successfully produces an executable, but it doesn't run
 right). Based on what type of bug it is, follow the instructions in the
 linked section to narrow down the bug so that the person who fixes it will be
 able to find the problem more easily.
 
 Once you have a reduced test-case, go to `the LLVM Bug Tracking System
-<https://bugs.llvm.org/enter_bug.cgi>`_ and fill out the form with the
-necessary details (note that you don't need to pick a category, just use
-the "new-bugs" category if you're not sure).  The bug description should
-contain the following information:
+<https://github.com/llvm/llvm-project/issues>`_ and fill out the form with the
+necessary details (note that you don't need to pick a label, just use if you're
+not sure).  The bug description should contain the following information:
 
 * All information necessary to reproduce the problem.
 * The reduced test-case that triggers the bug.
 * The location where you obtained LLVM (if not from our Git
   repository).
 
 Thanks for helping us make LLVM better!