Replace Ubuntu 20.04 with 24.04 for Docker base images

[ycombinator]

Describe the enhancement:

Ubuntu 20.04's standard support ends in April 2025. Before then, we should change our Docker base images to use Ubuntu 24.04 instead.

Describe a specific use case for the enhancement or feature:

To use a supported base image for our Docker images.

What is the definition of done?

Elastic Agent's Ubuntu-based Docker images use Ubuntu 24.04

[jlind23]

FWIW looks like Elastic-Agent changes have to happen in two different places:

• https://github.com/elastic/elastic-agent/blob/main/pkg/testing/define/batch_test.go
• https://github.com/elastic/elastic-agent/blob/main/dev-tools/packaging/packages.yml

[jlind23]

@cmacknz would 22.04 be the right call or shall we directly jump to 24.04?

[ycombinator]

Discussed in a leads meeting today and the decision was to jump directly to 24.04. Updated the issue title and description accordingly.