Enhancement: Run tests on PHP 8.0

[localheinz]

This PR

• runs tests on PHP 8.0

Follows #294.

[codecov]

Codecov Report

Merging #323 (da61218) into main (5f78aa4) will not change coverage.
The diff coverage is n/a.

❗ Current head da61218 differs from pull request most recent head 30c8cf2. Consider uploading reports for the commit 30c8cf2 to get more accurate results

@@            Coverage Diff            @@
##               main     #323   +/-   ##
=========================================
  Coverage     83.93%   83.93%           
  Complexity      151      151           
=========================================
  Files            23       23           
  Lines           498      498           
=========================================
  Hits            418      418           
  Misses           80       80           

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[ergebnis-bot]

Since this pull request has not had any activity within the last 180 days, I have marked it as stale.

I will close it if no further activity occurs within the next 14 days.