[llvm] [QualGroup][docs] Update meeting schedule and link for slides (PR #169458)

[Zaky Hermawan via llvm-commits]

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ZakyHermawan wrote:

This causing error "Inline emphasis start-string without end-string". I think thats because of underscore after the second asterisk. I changed it to `*YYYYMM*\_llvm_qual_wg` to keep the emphasis on `YYYYMM` only

https://github.com/llvm/llvm-project/pull/169458