doc: add release badge in README [ci skip]

Signed-off-by: Zespre Schmidt <[email protected]>

README.md

@@ -1,6 +1,7 @@
 # KubeVirtBMC
 
 [![main build and publish workflow](https://github.com/starbops/kubevirtbmc/actions/workflows/main.yml/badge.svg)](https://github.com/starbops/kubevirtbmc/actions/workflows/main.yml)
+[![release](https://img.shields.io/github/v/release/starbops/kubevirtbmc)](https://github.com/starbops/kubevirtbmc/releases)
 
 KubeVirtBMC unleashes the power management for virtual machines on Kubernetes in a traditional way, i.e., [IPMI](https://www.intel.com.tw/content/www/tw/zh/products/docs/servers/ipmi/ipmi-second-gen-interface-spec-v2-rev1-1.html). This allows users to power on/off/reset and set the boot device for the VM. It was initially designed for [Tinkerbell](https://github.com/tinkerbell/tink)/[Seeder](https://github.com/harvester/seeder) to provision [KubeVirt](https://github.com/kubevirt/kubevirt) VMs, just like we did in the good old days.