Remove img.with-border style

The border was barely visible, was only used in a single place,
and didn't add much.

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

_scss/_overrides.scss

@@ -116,10 +116,6 @@ a.gs-title {
     background: transparent;
 }
 
-img.with-border {
-  border: 1px solid #eaeaea;
-}
-
 input.gsc-search-button, input.gsc-search-button:hover, input.gsc-search-button:focus {
   display: none!important;
 }

docker-for-mac/index.md

@@ -234,8 +234,7 @@ experience conflicts, remove `/usr/local/bin/kubectl`.
   The status of Kubernetes shows in the Docker menu and the context points to
   `docker-desktop`.
 
-  ![Docker Menu with Kubernetes](images/kubernetes/kube-context.png){: .with-border
-  width="400px"}
+  ![Docker Menu with Kubernetes](images/kubernetes/kube-context.png){: width="400px"}
 
 - By default, Kubernetes containers are hidden from commands like `docker
   service ls`, because managing them manually is not supported. To make them