Add support for alpine 3.23

[sireeshajonnalagadda]

Devcontainer name

base-alpine
Description

This PR adds 3.23 latest alpine version to the supported versions list in base-alpine image.
Changelog

Changes are there in manifest.json, Dockerfile and readme.md file for base-alpine image to add support for the latest 3.23 alpine version.
Checklist

Checked that applied changes work as expected.

[Copilot]

Pull request overview

This PR adds support for Alpine 3.23 to the base-alpine devcontainer image. The changes include adding the new variant to the manifest, updating documentation, and setting Alpine 3.23 as the default version. The version is bumped from 2.0.2 to 3.0.0, which is appropriate given that changing the default Alpine version constitutes a breaking change.

Key changes:

• Major version bump to 3.0.0 due to changing the default Alpine version from 3.22 to 3.23
• Alpine 3.23 added as a supported variant and set as the default in variantTags
• Documentation updated to reflect the new variant and version

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 2 comments.

File	Description
src/base-alpine/manifest.json	Bumps version to 3.0.0, adds 3.23 to variants list, and updates variantTags to make 3.23 the default
src/base-alpine/README.md	Adds alpine-3.23 to variant list and image references, updates semantic version examples from 1.x to 3.x
src/base-alpine/.devcontainer/Dockerfile	Updates default VARIANT argument from 3.22 to 3.23

[Copilot]

Per the custom guideline for image changes, when adding a new variant that becomes the latest stable version (not a preview), the variant should be set as "latest" in the manifest. Since Alpine 3.23 is now the newest stable version and is being used as the default in the Dockerfile, consider whether build.latest should be set to "3.23" instead of remaining false. This follows the pattern from other multi-variant images where the newest variant is marked as latest (e.g., base-debian with "latest": "trixie").