[doc] Align agents logs documentation

[SylvainJuge]

update logs docs for java agent, part of elastic/apm#800

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• Start Time: 2023-06-07T15:39:17.589+0000

• Duration: 3 min 30 sec

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[SylvainJuge]

@elasticmachine run elasticsearch-ci/docs

[SylvainJuge]

@elasticmachine run elasticsearch-ci/docs

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/test