bug(ubuntu): Trivy doesn't support Ubuntu 20.04-ESM

[DmitriyLewen]

Description

Ubuntu finished base support for ubuntu 20.04.
But Ubuntu still support 20.04 for Ubuntu Pro (ESM).

Required changes:

• Add advisories for 20.04-ESM in Trivy-db (feat(ubuntu): add support 20.04-ESM trivy-db#540)
• Add 20.04-ESM into EOL dates in Trivy (feat(ubuntu): add eol date for 20.04-ESM #8981)

Discussed in #8977

[DmitriyLewen]

We added advisories for 20.04-ESM - aquasecurity/trivy-db#540
So now Trivy detects vulnerabilities for 20.04-ESM.

EOL warning will be removed in v0.64.0 Trivy release.