Add vpc label to docs.
@@ -444,6 +444,7 @@ The following meta labels are available on targets during [relabeling](#relabel_
* `__meta_digitalocean_status`: the status of the droplet
* `__meta_digitalocean_features`: the comma-separated list of features of the droplet
* `__meta_digitalocean_tags`: the comma-separated list of tags of the droplet
+* `__meta_digitalocean_vpc`: the id of the droplet's VPC
```yaml
# Authentication information used to authenticate to the API server.
