[clang] [clang-tools-extra] [clangd][HLSL] Fix register attribute source range for hover inside arguments (PR #212881)

[Finn Plummer via cfe-commits]

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@@ -5311,6 +5311,30 @@ TEST(Hover, FunctionParameters) {
   }
 }
 
+TEST(Hover, HLSLRegisterAttributeRange) {
+  Annotations T(R"cpp(
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inbelic wrote:

Not to suggest we shouldn't have cpp tests as well

https://github.com/llvm/llvm-project/pull/212881