[clang] [clang][ssaf] Add accessor for `LUNamespace` (PR #195756)

[Balázs Benics via cfe-commits]

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@@ -8,6 +8,7 @@ add_distinct_clang_unittest(ClangScalableAnalysisTests
   EntityLinkageTest.cpp
   EntityLinkerTest.cpp
   EntityNameTest.cpp
+  LUSummaryTest.cpp
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steakhal wrote:

🤔  I wonder how did this (`L`) end up between two `E`s.

https://github.com/llvm/llvm-project/pull/195756