Use PHP 8.0 in contained dockerfile

[cedricziel]

The extension relies on PHP 8

[codecov]

Codecov Report

Merging #142 (7ea6ca6) into main (f897e94) will increase coverage by 4.92%.
The diff coverage is n/a.

❗ Current head 7ea6ca6 differs from pull request most recent head 1eafda9. Consider uploading reports for the commit 1eafda9 to get more accurate results

Additional details and impacted files

@@             Coverage Diff              @@
##               main     #142      +/-   ##
============================================
+ Coverage     25.03%   29.95%   +4.92%     
+ Complexity      315      265      -50     
============================================
  Files            32       28       -4     
  Lines          1306      998     -308     
============================================
- Hits            327      299      -28     
+ Misses          979      699     -280     

Flag	Coverage Δ
7.4	72.04% <ø> (ø)
8.0	0.00% <ø> (-29.35%)	⬇️
8.1	0.00% <ø> (-29.44%)	⬇️
8.2	0.00% <ø> (-25.06%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

see 4 files with indirect coverage changes

---

Continue to review full report in Codecov by Sentry.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update f897e94...1eafda9. Read the comment docs.