Fix multiarch + Add bash_unit for testing

[mistraloz]

Summary

Fix multi arch troubles and lot of related things (becareful : it's a risky PR, especialy, tini is removed and it was directly related to the entrypoint).

This PR fixes/implements :

• Fix php extensions defined in the PHP_EXTENSIONS environment variable are not installed #329
• Fix ini file doesn't exist under /etc/php/8.1/mods-available #327
• Fix Docker container build fails #324
• Fix SOAP extension is missing for PHP 8.0 CLI image #331
• Change testing suite for bash unit (old suite is keep and deprecated). It's allow more clear view of errors, to play only one part of tests, faster tests and it's more easy to add some
• Force php-swoole to v4 for php 7.*
• Add blackfire for php8.1 (and fix a wrong installation pattern)
• Lot of fixes about php extensions who missing or installed by pecl/pickle instead of apt

Checklist

• I followed the guidelines in CONTRIBUTING guide
• I have squashed any insignificant commits
• This change has comments for package types, values, functions, and non-obvious lines of code

TODO

Theses changes are not included in this PR (already so big) but FYI :

• more work is required to speed up build and test (especialy for ARM)
• some changes should be required for optimise building stages in ci (test one version before all other to avoid spaming, synchronize cache between step... or any other idea to allow more accurate testing)
• Some php extensions are removed into arm because the build time is too long for them : swoole, rdkafka, ev and snmp.
• Tini is disabled (as hot fix) because it's does work properly in arm build. It's may a good idea to double check if there is a breaking change (PR Run Apache2 in background #215 may help to find a smart fix).
• There is too much extensions onto fat images, and too much variants. We should find a way to avoid that to allow a more new features and an easier maintenance.