Fix OTel span end with explicit timestamp

[SylvainJuge]

What does this PR do?

fixes OTel bridge span not properly ended when using an explicit timestamp.

Checklist

• This is a bugfix
  • I have updated CHANGELOG.asciidoc
  • I have added tests that would fail without this fix

[github-actions]

/test

[ghost]

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Build stats

• Start Time: 2022-05-04T08:12:46.441+0000

• Duration: 44 min 20 sec

Test stats 🧪

Test	Results
Failed	0
Passed	2862
Skipped	21
Total	2883

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