[llvm] [Docs] Update security response group with vendor observer. (PR #224044)

[George Burgess IV via llvm-commits]

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@@ -32,8 +32,7 @@ Security Response Group Members
 
 The members of the group represent a wide cross-section of the community, and
 meet the criteria for inclusion below. The list is in the format
-`* ${full_name} (${affiliation}) [${github_username}]`. If a github
-username for an individual isn't available, the brackets will be empty.
+`* ${full_name} (${affiliation}) [${github_username}]`.
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gburgessiv wrote:

LGTM, thanks!

https://github.com/llvm/llvm-project/pull/224044