Update docs/Coding style.md
Fix duplicated word.
@@ -153,7 +153,7 @@ C++ code
explicitly expresss lifetime semantics.
- If required by a platform (e.g, Microsoft COM), use the appropriate
ref-counted type, but do not expose those types to platform agnostic code,
- prefer to use use an abstraction.
+ prefer to use an abstraction.
Python code
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