Merge pull request #420 from jacobweinstock/release-prep

Bump the API metadata.yaml:

## Description

<!--- Please describe what this PR is going to change -->
This is in preparation for the next release.

## Why is this needed

<!--- Link to issue you have raised -->

Fixes: #

## How Has This Been Tested?
<!--- Please describe in detail how you tested your changes. -->
<!--- Include details of your testing environment, and the tests you ran to -->
<!--- see how your change affects other areas of the code, etc. -->


## How are existing users impacted? What migration steps/scripts do we need?

<!--- Fixes a bug, unblocks installation, removes a component of the stack etc -->
<!--- Requires a DB migration script, etc. -->


## Checklist:

I have:

- [ ] updated the documentation and/or roadmap (if required)
- [ ] added unit or e2e tests
- [ ] provided instructions on how to upgrade

metadata.yaml

@@ -5,6 +5,9 @@
 # update this file only when a new major or minor version is released
 apiVersion: clusterctl.cluster.x-k8s.io/v1alpha3
 releaseSeries:
+  - major: 0
+    minor: 6
+    contract: v1beta1
   - major: 0
     minor: 5
     contract: v1beta1