[2.7] Improve security-scan's e2e validation with yamllint and kube-bench dry-run

[samjustus]

backport #227

[rishabhmsra]

Validated on rancher v2.7-head. Provisioned RKE1, RKE2 and K3s clusters using below k8s versions:

• v1.23
• v1.24
• v1.25
• v1.26

Ran the scans using respective profiles on all the clusters, all scan passed except below failures which are expected and will be release noted:

RKE1 k8s v1.26 hardened:

Mixed
4.1.7	Ensure that the certificate authorities file permissions are set to 600 or more restrictive (Automated)

RKE2 k8s v1.26 Failures in node driver, custom, local(non-hardened) clusters:

Fail
1.1.1	Ensure that the API server pod specification file permissions are set to 600 or more restrictive (Automated)
Fail
1.1.3	Ensure that the controller manager pod specification file permissions are set to 600 or more restrictive (Automated)
Fail
1.1.5	Ensure that the scheduler pod specification file permissions are set to 600 or more restrictive (Automated)
Fail
1.1.7	Ensure that the etcd pod specification file permissions are set to 600 or more restrictive (Automated)

RKE2 k8s v1.24 failures:

Fail
1.1.3	Ensure that the controller manager pod specification file permissions are set to 600 or more restrictive (Automated)
Fail
1.1.5	Ensure that the scheduler pod specification file permissions are set to 600 or more restrictive (Automated)