[Feature] Support init Containers

[yandongxiao]

Description

In some cases, we need to update the configuration of the host machine. For example, in order to collect Core Dump files, we need to set /proc/sys/kernel/core_pattern in the host environment. There are two options available:

1. Start StarRocks Component with privileged root permission and run it continuously with that permission. This requires the Operator to have the ability to change the entrypoint script.
2. Before starting StarRocks Component, start a privileged root init container first. This method provides higher security.

Checklist

For operator, please complete the following checklist:

• run make generate to generate the code.
• run golangci-lint run to check the code style.
• run make test to run UT.
• run make manifests to update the yaml files of CRD.

[dengliu]

@yandongxiao when will this be release in the helm chart and CRD?
cc @mingmxu

[yandongxiao]

‌‌Should be by the end of this week or early next week.