Update links

docs/concepts/stack/README.md

@@ -4,7 +4,7 @@ _Stack_ is one of the core concepts in Spacelift. A stack is an isolated, indepe
 
 Unless you're using Spacelift only to host and test private [Terraform modules](../../vendors/terraform/module-registry.md), your account should probably contain one or more stacks to be of any use. For example:
 
-![](<../../assets/screenshots/Screen Shot 2022-06-29 at 2.47.11 PM.png>)
+![](<../../assets/screenshots/stack/list.png>)
 
 Here's a few helpful articles about stacks:
 
@@ -18,6 +18,6 @@ Similar to [runs](../run/README.md) and [tasks](../run/task.md), stacks also hav
 A stack's state is the last state of its most recently processed [tracked run](../run/README.md#where-do-runs-come-from) that has progressed beyond the [queued](../run/README.md#queued) state and which was not [canceled](../run/README.md#canceled).
 Only if the stack has no runs yet a special state "None" is applied:
 
-![](<../../assets/screenshots/Stacks_·_spacelift-io (1).png>)
+![](<../../assets/screenshots/stack/none-stack-state.png>)
 
 Stack states allow users to see at a glance the overall health of their infrastructure, and the level of development activity associated with it.