Blender Git Loki

Cleanup: Use raw string literal

Resolves modernize-raw-string-literal Clang-Tidy warning

The way warning works is it suggests to use raw literal when
overhead of having escape characters is higher than the overhead
of having raw literal syntax (talking about code size overhead).
This means that the warning will not trigger for "foo"bar".

Differential Revision: https://developer.blender.org/D10322