correct for windows slashes in redirect `precompile`

lib/redirects/precompile.js

@@ -85,7 +85,7 @@ module.exports = async function precompileRedirects (pages) {
     // add a veriation like `/free-pro-team@latest/v3/gists/comments`;
     // again, we need to do this because all links in content get rewritten
     if (!developerRoute.startsWith('/enterprise/')) {
-      const developerRouteWithVersion = path.join(nonEnterpriseDefaultVersion, developerRoute)
+      const developerRouteWithVersion = slash(path.join(nonEnterpriseDefaultVersion, developerRoute))
       const developerRouteWithVersionAndLanguage = `/en/${developerRouteWithVersion}`
       allRedirects[developerRouteWithVersion] = newPath
       allRedirects[developerRouteWithVersionAndLanguage] = newPath