Update CHANGELOG for 8.0.0b1 release API changes
against kubernetes 1.12.1 release (temp 1.12.2 openapi spec)
**Bug Fix:**
- Update ExecProvider to use safe\_get() to tolerate kube-config file that sets
`args: null` and `env: null` [kubernetes-client/python-base#91](https://github.com/kubernetes-client/python-base/pull/91)
+- Properly deserialize API server's response when posting a deployment rollback [kubernetes/kubernetes#68909](https://github.com/kubernetes/kubernetes/pull/68909)
+
+**API Change:**
+- dry-run: CREATE/UPDATE/PATCH methods now support dryRun parameter [kubernetes/kubernetes#69359](https://github.com/kubernetes/kubernetes/pull/69359)
# v8.0.0a1
**New Feature:**
