docs(py-rattler): fix example path in mkdocs snippet (#814)

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Fixing the example in the quickstart

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py-rattler/docs/index.md

@@ -21,7 +21,7 @@ Py-rattler is the python bindings for rattler.
 Let's see an example to learn some of the functionality the library has to offer.
 
 ```python
---8<-- "examples\solve_and_install.py"
+--8<-- "examples/solve_and_install.py"
 ```
 
 Py-rattler provides friendly high level functions to download dependencies and create environments.