docs: document Debian lifecycle transitions

[MikeMcC399]

Description

CONTRIBUTING > Version Updates is updated with information concerning Debian releases and lifecycle transitions.

Motivation and Context

Debian release lifecycle transitions require re-configuration action of node Docker image variants.

CONTRIBUTING > Version Updates does not yet include any related description.

Debian Releases > Release life cycle states:

Debian announces its new stable release on a regular basis. The Debian release life cycle encompasses five years: the first three years of full support followed by two years of Long Term Support (LTS).

• Release
• End of Life (EOL) after 3 years
• End of LTS after another 2 years, 5 years in total

When Debian transitions from EOL to LTS, the LTS support team defines and publishes LTS support architectures that may be only a subset of the architectures supported during the original release phase.

Testing Details

Types of changes

• Documentation
• Version change (Update, remove or add more Node.js versions)
• Variant change (Update, remove or add more variants, or versions of variants)
• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Other (none of the above)

Checklist

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING.md document.
• All new and existing tests passed.

[MikeMcC399]

See #2610 for unrelated fix to markdown-link-check failure.