fix: sesgithub link

src/content/docs/about/runtime-environment.md

@@ -50,6 +50,6 @@ As a result, to secure your code in the browser, you need to use one of the supp
 [lavamoat-node]: /guides/lavamoat-node
 [lavamoat-browserify]: /guides/browserify
 [lavamoat-webpack]: /guides/webpack
-[sesgithub]: https://github.com/endojs/endo/tree/master/package/ses
+[sesgithub]: https://github.com/endojs/endo/tree/master/packages/ses
 [policydoc]: /reference/policy
 [sescomputingguide]: https://github.com/endojs/endo/blob/master/packages/ses/docs/secure-coding-guide.md