[clang] [clang][www] Fix typos in OpenProjects page (PR #228822)

[Ivy Xu via cfe-commits]

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@@ -37,15 +37,15 @@ <h1>Open Clang Projects</h1>
      undocumented attributes</a>,</li>
   <li>documenting <a href="https://github.com/llvm/llvm-project/blob/main/clang/include/clang/Basic/DiagnosticDocs.td">
       diagnostic group flags</a> (adding code examples of what is diagnosed, or
-      other relevant information), or</li>
+      other relevant information),</li>
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IvyXu420 wrote:

Yes. I think it would be better to keep a single "or" here.

https://github.com/llvm/llvm-project/pull/228822