Add docs for new settings in v1.50.0 and v1.51.0 #559

Bottlerocket v1.50.0 and v1.51.0 released the following new k8s settings which need documentation:

• kube-reserved.pid
• system-reserved.pid
• image-minimum-gc-age
• image-maximum-gc-age
• max-parallel-image-pulls
• ids-per-pod
• Beta options for cpu-manager-policy-options