Drop references to external secret stores and controller configs

Both removed in Crossplane v2

Signed-off-by: Nic Cope <[email protected]>

Author: negz

content/v2.0-preview/cli/command-reference.md

@@ -514,9 +514,8 @@ As Crossplane evolves, its APIs and resources may change. To help with the
 migration to the new APIs and resources, the `crossplane beta convert` command
 converts a Crossplane resource to a new version or kind.
 
-Use the `crossplane beta convert` command to convert an existing
-[ControllerConfig]({{<ref "../concepts/providers#controller-configuration">}})
-to a [DeploymentRuntimeConfig]({{<ref "../concepts/providers#runtime-configuration">}}) 
+Use the `crossplane beta convert` command to convert a
+ControllerConfig to a [DeploymentRuntimeConfig]({{<ref "../concepts/providers#runtime-configuration">}}) 
 or a legacy Composition using `mode: Resources` to a 
 [Composition pipeline function]({{< ref "../concepts/compositions" >}}).
 

content/v2.0-preview/concepts/composite-resources.md

@@ -317,33 +317,6 @@ spec:
   # Removed for brevity
 ```
 
-Composite resources can write connection secrets to an 
-[external secret store]({{<ref "../guides/vault-as-secret-store">}}),
-like HashiCorp Vault. 
-
-{{<hint "important" >}}
-External secret stores are an alpha feature. Alpha features aren't enabled by
-default. 
-{{< /hint >}}
-
-Use the {{<hover label="publishsecret"
-line="6">}}publishConnectionDetailsTo{{</hover>}} field to save connection
-secrets to an external secrets store.
-
-```yaml {label="publishsecret",copy-lines="none"}
-apiVersion: example.org/v1alpha1
-kind: xMyDatabase
-metadata:
-  name: my-composite-resource
-spec:
-  publishConnectionDetailsTo:
-    name: my-external-secret-store
-  # Removed for brevity
-```
-
-Read the [External Secrets Store]({{<ref "../guides/vault-as-secret-store">}}) documentation for more information on using
-external secret stores. 
-
 For more information on connection secrets read the [Connection Secrets knowledge base article]({{<ref "connection-details">}}).
 
 ### Pausing composite resources