docs: remove redundant description about env vars

`Environment Variables` appeared twice in
https://lima-vm.io/docs/config/

Signed-off-by: Akihiro Suda <akihiro.suda.cz@hco.ntt.co.jp>

Author: AkihiroSuda

website/content/en/docs/config/_index.md

@@ -12,5 +12,3 @@ The current default spec:
 - Disk: 100 GiB
 - Mounts: `~` (read-only), `/tmp/lima` (writable; removed in Lima v2.0)
 - SSH: 127.0.0.1:<Random port>
-
-For environment variables, see [Environment Variables](./environment-variables/).