Linux Audit feature in Node-agent

[slashben]

This pull request adds support for Linux audit rule monitoring to the Kubescape Operator Helm chart. The main changes introduce a new capability flag for Linux audit, a corresponding CustomResourceDefinition (CRD) for managing audit rules, configuration options for the node agent, and necessary RBAC and container permissions. Additionally, several default capabilities are disabled to focus on audit-related features.

Linux Audit Capability and CRD:

• Added a new linuxAudit capability flag to values.yaml, enabled by default, to control Linux audit monitoring features.
• Introduced a comprehensive LinuxAuditRule CRD (linuxauditrule.crd.yaml) for defining and managing audit rules, including file, syscall, network, and process monitoring.

Node Agent Configuration and Permissions:

• Updated the node agent's configmap (node-agent/configmap.yaml) to include audit detection settings and event filtering, which are conditionally enabled based on the linuxAudit flag.
• Added required audit-related container capabilities (AUDIT_READ, AUDIT_WRITE, AUDIT_CONTROL) to the node agent's daemonset when Linux audit is enabled.
• Changed the node agent image repository and tag to a test version, and set the image pull policy to Always for development purposes.

Default Capability Adjustments:

• Disabled several unrelated default capabilities (configuration scanning, vulnerability scanning, network policy, seccomp, etc.) in values.yaml to streamline the chart for audit-specific testing or deployment.

Node Agent Audit Detection Options:

• Added configurable audit detection exporters and event type filters under the node agent’s config section in values.yaml, allowing for flexible audit event handling and output.