Add STACKIT to readme (#2988)

* Add STACKIT to readme

and sort CSPs alphabetically in sentences

* fix links

docs/versioned_docs/version-2.13/getting-started/install.md

@@ -11,7 +11,7 @@ Make sure the following requirements are met:
 - Your machine is running Linux or macOS
 - You have admin rights on your machine
 - [kubectl](https://kubernetes.io/docs/tasks/tools/) is installed
-- Your CSP is Microsoft Azure, Google Cloud Platform (GCP), or Amazon Web Services (AWS)
+- Your CSP is Amazon Web Services (AWS), Microsoft Azure, or Google Cloud Platform (GCP)
 
 ## Install the Constellation CLI
 
@@ -52,7 +52,6 @@ curl -LO https://github.com/edgelesssys/constellation/releases/latest/download/c
 sudo install constellation-linux-arm64 /usr/local/bin/constellation
 ```
 
-
 </tabItem>
 
 <tabItem value="darwin-arm64" label="macOS (Apple Silicon)">
@@ -71,8 +70,6 @@ curl -LO https://github.com/edgelesssys/constellation/releases/latest/download/c
 sudo install constellation-darwin-arm64 /usr/local/bin/constellation
 ```
 
-
-
 </tabItem>
 
 <tabItem value="darwin-amd64" label="macOS (Intel)">
@@ -281,7 +278,6 @@ The built-in `AdministratorAccess` policy is a superset of these permissions.
 
 To [create a Constellation cluster](../workflows/create.md#the-create-step), see the permissions of [main.tf](https://github.com/edgelesssys/constellation/blob/main/terraform/infrastructure/iam/aws/main.tf).
 
-
 The built-in `PowerUserAccess` policy is a superset of these permissions.
 
 Follow Amazon's guide on [understanding](https://docs.aws.amazon.com/IAM/latest/UserGuide/access_policies.html) and [managing policies](https://docs.aws.amazon.com/IAM/latest/UserGuide/access_policies_managed-vs-inline.html).
@@ -357,7 +353,6 @@ Options and first steps are described in the [AWS CLI documentation](https://doc
 
 </tabItem>
 
-
 </tabs>
 
 ## Next steps