[Fleet] Fix docker publish

[nchaulet]

Description

The docker publish seems to be broken after #2832

That PR fix docker publish step to remove the docker tag command that is not used anymore.

[elasticmachine]

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• Start Time: 2023-07-27T12:18:47.981+0000

• Duration: 38 min 0 sec

Test stats 🧪

Test	Results
Failed	0
Passed	751
Skipped	1
Total	752

💚 Flaky test report

Tests succeeded.

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