Update quickstart.md

docs/quickstart.md

@@ -55,7 +55,6 @@ A [topology definition deep-dive](manual/topo-def-file.md) document provides a c
 * The actual [nodes](manual/nodes.md) of the topology are defined in the `nodes` section which holds a map of node names. In the example above, nodes with names `srl` and `ceos` are defined.
 * Node elements must have a `kind` parameter to indicate which kind this node belongs to. Under the nodes section you typically provide node-specific parameters. This lab uses a node-specific parameters - `image`.  
 * `nodes` are interconnected with `links`. Each `link` is [defined](manual/topo-def-file.md#links) by a set of `endpoints`.
-* It supports environment variable expansion. You can specify environment variable like this `${YOUR_ENV_VAR}`.
 
 ## Container image
 One of node's most important properties is the container [`image`](manual/nodes.md#image) they use. In our example the nodes use a specific image which we imported upfront[^2].
@@ -157,4 +156,4 @@ To get a broader view on the containerlab features and components, refer to the
 Do not forget to check out the [Lab examples](lab-examples/lab-examples.md) section where we provide complete and ready-to-run topology definition files. This is a great starting point to explore containerlab by doing.
 
 [^1]: For other installation options such as package managers, manual binary downloads or instructions to get containerlab for non-RHEL/Debian distros, refer to the [installation guide](install.md).
-[^2]: Containerlab would try to pull the images upon the lab deployment, but if the images are not available publicly or you do not have the private repositories configured, then you need to import the images upfront.
+[^2]: Containerlab would try to pull the images upon the lab deployment, but if the images are not available publicly or you do not have the private repositories configured, then you need to import the images upfront.