docs: update crd version in getting started guide (#485)

Author: james-milligan

docs/getting_started.md

@@ -37,12 +37,12 @@ spec:
 The `FlagSourceConfiguration` defined below can be used to assign the `FeatureFlagConfiguration`, as well as any other configuration settings, to the injected sidecars. In this example, the port exposed by the injected container is also set.
 
 ```yaml
-apiVersion: core.openfeature.dev/v1alpha2
+apiVersion: core.openfeature.dev/v1alpha3
 kind: FlagSourceConfiguration
 metadata:
   name: flagsourceconfiguration-sample
 spec:
-  syncProviders:
+  sources:
   - source: featureflagconfiguration-sample
     provider: kubernetes
   port: 8080