Add note about windows paths (softprops#340)

* Add note about windows paths

softprops#280

Document change in glob 8.0

* Fix incorrectly escaped markdown backslashes

README.md

@@ -128,6 +128,8 @@ jobs:
 
 > **⚠️ Note:** Notice the `|` in the yaml syntax above ☝️. That let's you effectively declare a multi-line yaml string. You can learn more about multi-line yaml syntax [here](https://yaml-multiline.info)
 
+> **⚠️ Note for Windows:** Paths must use `/` as a separator, not `\`, as `\` is used to escape characters with special meaning in the pattern; for example, instead of specifying `D:\Foo.txt`, you must specify `D:/Foo.txt`. If you're using PowerShell, you can do this with `$Path = $Path -replace '\\','/'`
+
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