bump default coredns image to v1.11.3 (because previous ones had CVEs)

[hidalgopl]

What issue type does this pull request address? (keep at least one, remove the others)
/kind bugfix

What does this pull request do? Which issues does it resolve? (use resolves #<issue_number> if possible)
It updates default coredns image to 1.11.3, which has no CVEs and adds e2e tests to verify if pinned version is used:

trivy image coredns/coredns:1.11.3 --severity HIGH,CRITICAL

2024-08-05T08:51:42.727+0200	INFO	Vulnerability scanning is enabled
2024-08-05T08:51:42.727+0200	INFO	Secret scanning is enabled
2024-08-05T08:51:42.727+0200	INFO	If your scanning is slow, please try '--security-checks vuln' to disable secret scanning
2024-08-05T08:51:42.727+0200	INFO	Please see also https://aquasecurity.github.io/trivy/v0.35/docs/secret/scanning/#recommendation for faster secret detection
2024-08-05T08:51:44.885+0200	INFO	Detected OS: debian
2024-08-05T08:51:44.885+0200	INFO	Detecting Debian vulnerabilities...
2024-08-05T08:51:44.885+0200	INFO	Number of language-specific files: 1
2024-08-05T08:51:44.885+0200	INFO	Detecting gobinary vulnerabilities...

coredns/coredns:1.11.3 (debian 11.10)

Total: 0 (HIGH: 0, CRITICAL: 0)

resolves ENG-3849

Please provide a short message that should be published in the vcluster release notes
Bumped CoreDNS image to v1.11.3

What else do we need to know?

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