Fix vertx3 tests

[SylvainJuge]

What does this PR do?

Fixes the vertx3 tests failures

We have a floating dependency version on vertx-junit, and the latest 4.x version is not compatible anymore with 3.x.
As this is only for testing, sticking to an older version for vertx3 should be fine for now.

Checklist

• This is something else
  • I have updated CHANGELOG.asciidoc

[apmmachine]

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Build stats

• Start Time: 2023-03-02T10:18:45.388+0000

• Duration: 60 min 23 sec

Test stats 🧪

Test	Results
Failed	0
Passed	3553
Skipped	121
Total	3674

💚 Flaky test report

Tests succeeded.

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