Add simple performance tests

[swissspidy]

No description provided.

[codecov]

Codecov Report

Merging #862 (484bfb4) into main (9b57dd9) will not change coverage.
Report is 7 commits behind head on main.
The diff coverage is n/a.

@@           Coverage Diff           @@
##             main     #862   +/-   ##
=======================================
  Coverage   95.86%   95.86%           
=======================================
  Files           5        5           
  Lines         580      580           
  Branches       31       31           
=======================================
  Hits          556      556           
  Misses         24       24           

Flag	Coverage Δ
default	87.14% <ø> (ø)
js	100.00% <ø> (ø)
multisite	90.95% <ø> (ø)

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