fix: use different tests for the demos

[kuisathaverat]

What does this PR do?

• It uses a new set of tests for the demos.

Why is it important?

Before this change we use the pytest-otel tests for the demos, we can no longer use those tests because we use the In-Memory Otel exporter and a file to check the plugin behavior, this causes not all the traces to be reported to the demo. Using a simpler test suit for the demos fixes the issue.

[apmmachine]

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• Reason: null

• Start Time: 2022-02-01T12:20:44.015+0000

• Duration: 12 min 33 sec

• Commit: 23d769a

Test stats 🧪

Test	Results
Failed	0
Passed	1336
Skipped	2
Total	1338

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