[clang] [clang][analyzer] Move checker alpha.unix.StdCLibraryFunctions out of alpha. (PR #66207)

[Balazs Benics via cfe-commits]

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@@ -1026,6 +1026,100 @@ Check for null pointers being passed as arguments to C string functions:
    return strlen(0); // warn
  }
 
+.. _unix-StdCLibraryFunctions:
+
+unix.StdCLibraryFunctions (C)
+"""""""""""""""""""""""""""""""""""
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steakhal wrote:

Align this with the section title.

https://github.com/llvm/llvm-project/pull/66207