chore: update Alpine to 3.23.3 and fix features

[sjinks]

This pull request updates the Alpine base image and improves PHP and Xdebug devcontainer features. The main changes include upgrading the Alpine version, updating PHP and Xdebug feature versions, adjusting package repository usage, and making minor improvements to environment variable formatting and symlink creation.

Base image and environment updates:

• Upgraded the Alpine base image from version 3.22.2 to 3.23.3 in Dockerfile, and updated the image version in .devcontainer.json to 1.12.0. Also standardized environment variable assignments to use =. [1] [2] [3]

PHP feature improvements:

• Updated the PHP devcontainer feature version to 2.10.0 and set the default intelephense.environment.phpVersion to 8.3.0. [1] [2]
• Adjusted install.sh for PHP 8.2 and 8.4 to explicitly use the Alpine 3.22 community repository for package installs where needed, and removed conditional repository logic for PHP 8.4. [1] [2] [3]
• Improved symlink creation for PHP 8.4 binaries by using the -sf flags with ln for force and symbolic linking.

Xdebug feature improvements:

• Updated the Xdebug devcontainer feature version to 1.7.0.
• Updated Xdebug installation scripts to use the Alpine 3.22 community repository for PHP 8.2, and simplified repository handling for PHP 8.4. [1] [2]