[clang-tools-extra] [clang-tidy] Improve documentation of bugprone-pointer-arithmetic-on-polymorphic-object (PR #108324)

[Nicolas van Kempen via cfe-commits]

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@@ -19,20 +19,23 @@ Example:
 .. code-block:: c++
 
   struct Base {
-    virtual void ~Base();
+    virtual ~Base();
+    int i;
   };
-
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nicovank wrote:

Sorry I wasn't clear, I meant to keep the spacing here between structs/functions, but when there is a blank line to not have any whitespace characters on it ('' vs '  '). A couple blanks lines in this first block between structs/functions and LGTM!

https://github.com/llvm/llvm-project/pull/108324