Minor readability improvement for README-contributing.md

Author: slouken

docs/README-contributing.md

@@ -57,7 +57,7 @@ If you had already forked the repository, you may update it from the web page us
 
 Code formatting is done using a custom `.clang-format` file, you can learn more about how to run it [here](https://clang.llvm.org/docs/ClangFormat.html).
 
-Some legacy code may not be formatted, as such avoid formatting the whole file at once and only format around your changes.
+Some legacy code may not be formatted, so please avoid formatting the whole file at once and only format around your changes.
 
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