Fix opening files with explorer in WSL

The OS command to open file in explorer in WSL doesn't currently work as
expected; it always opens the file explorer at the default opening
location. This is because the {{filename}} variable returns the path in
WSL format, and not in the format expected by Windows.

We use wslpath, a utility shipped with WSL, to make the path conversion.

pkg/config/config_linux.go

@@ -21,7 +21,7 @@ func isContainer() bool {
 func GetPlatformDefaultConfig() OSConfig {
 	if isWSL() && !isContainer() {
 		return OSConfig{
-			Open:     `powershell.exe start explorer.exe {{filename}} >/dev/null`,
+			Open:     `powershell.exe start explorer.exe "$(wslpath -w {{filename}})" >/dev/null`,
 			OpenLink: `powershell.exe start {{link}} >/dev/null`,
 		}
 	}