feat: support lts releases in linux

[risu729]

Since version-fox#13 hasn't been merged for a week, I'm opening the same PR here.

I created a new branch from the latest commit of version-fox/vfox-php, so I think we need to sync the fork before merging this to see the actual change of this PR.

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It was unable to install LTS versions of PHP because it was not listed in https://www.php.net/releases/, which only includes "Unsupported Historical Releases".

$ vfox --debug install [email protected]
CallFunction: PreInstall
plugin [PreInstall] method error: /home/risu/.version-fox/plugin/php/hooks/pre_install.lua:31: version not found for provided version 8.4.8
stack traceback:
        [G]: in function 'error'
        /home/risu/.version-fox/plugin/php/hooks/pre_install.lua:31: in main chunk
        [G]: ?
failed to install php

This PR adds https://www.php.net/downloads.php as the source of versions to support LTS versions.