[Release] Update version to 8.10.4

[elasticmachine]

Updates references to the new release 8.10.4.

Merge after the release 8.10.3.

[elasticmachine]

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Build stats

• Start Time: 2023-10-11T09:21:59.041+0000

• Duration: 26 min 48 sec

Test stats 🧪

Test	Results
Failed	0
Passed	6277
Skipped	55
Total	6332

💚 Flaky test report

Tests succeeded.

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To re-run your PR in the CI, just comment with:

• /test : Re-trigger the build.

• /package : Generate the packages.

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[elasticmachine]

🌐 Coverage report

Name	Metrics % (covered/total)	Diff
Packages	98.765% (80/81)	👍
Files	67.596% (194/287)	👍
Classes	66.234% (357/539)	👍
Methods	53.008% (1119/2111)	👍
Lines	38.526% (12717/33009)	👎 -0.03
Conditionals	100.0% (0/0)	💚

[pierrehilbert]

buildkite test this

[pchila]

The DEBUG commit has to be removed before merging
(it has been added to understand what is happening with agent packaging)

[pierrehilbert]

And now that's working...

[elasticmachine]

💚 Build Succeeded

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Build stats

• Start Time: 2023-10-11T11:17:50.440+0000

• Duration: 27 min 47 sec

Test stats 🧪

Test	Results
Failed	0
Passed	6317
Skipped	55
Total	6372

💚 Flaky test report

Tests succeeded.

🤖 GitHub comments

Expand to view the GitHub comments

To re-run your PR in the CI, just comment with:

• /test : Re-trigger the build.

• /package : Generate the packages.

• run integration tests : Run the Elastic Agent Integration tests.

• run end-to-end tests : Generate the packages and run the E2E Tests.

• run elasticsearch-ci/docs : Re-trigger the docs validation. (use unformatted text in the comment!)

[elasticmachine]

🌐 Coverage report

Name	Metrics % (covered/total)	Diff
Packages	98.765% (80/81)	👍
Files	67.944% (195/287)	👍 0.348
Classes	66.234% (357/539)	👍
Methods	53.125% (1122/2112)	👍 0.117
Lines	38.599% (12757/33050)	👍 0.043
Conditionals	100.0% (0/0)	💚