[Release] Update version to 8.10.3

[elasticmachine]

Updates references to the new release 8.10.3.

Merge after the release 8.10.2.

[elasticmachine]

💚 Build Succeeded

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• Start Time: 2023-09-21T08:10:00.097+0000

• Duration: 28 min 4 sec

Test stats 🧪

Test	Results
Failed	0
Passed	6251
Skipped	57
Total	6308

💚 Flaky test report

Tests succeeded.

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[elasticmachine]

🌐 Coverage report

Name	Metrics % (covered/total)	Diff
Packages	98.765% (80/81)	👍
Files	67.719% (193/285)	👍
Classes	66.292% (354/534)	👍
Methods	53.003% (1112/2098)	👍
Lines	38.603% (12670/32821)	👎 -0.015
Conditionals	100.0% (0/0)	💚

[mergify]

This pull request is now in conflicts. Could you fix it? 🙏
To fixup this pull request, you can check out it locally. See documentation: https://help.github.com/articles/checking-out-pull-requests-locally/

git fetch upstream
git checkout -b update-version-next-8.10.3 upstream/update-version-next-8.10.3
git merge upstream/8.10
git push upstream update-version-next-8.10.3