add support for new timestamp format

[ritalwar]

• Enhancement

What does this PR do?

This PR supports RabbitMQ new timestamp format with nanosecond precision and timezone "2022-03-23 13:16:58.000369+03:00".
Previous timestamp format "2019-04-12 10:11:15.094".
New DATETIME pattern is replaced by TIMESTAMP_ISO8601.

Why is it important?

This change is required as latest rabbitmq version switched to new default timestamp format.

Checklist

• My code follows the style guidelines of this project
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• I have made corresponding change to the default configuration files
• I have added tests that prove my fix is effective or that my feature works
• I have added an entry in CHANGELOG.next.asciidoc or CHANGELOG-developer.next.asciidoc.

Related issues

• Closes #Add support of a new RabbitMQ timestamp format integrations#2905
• Relates #Add support of a new RabbitMQ timestamp format integrations#2905

Logs

[mergify]

This pull request does not have a backport label.
If this is a bug or security fix, could you label this PR @ritalwar? 🙏.
For such, you'll need to label your PR with:

• The upcoming major version of the Elastic Stack
• The upcoming minor version of the Elastic Stack (if you're not pushing a breaking change)

To fixup this pull request, you need to add the backport labels for the needed
branches, such as:

• backport-v8./d.0 is the label to automatically backport to the 8./d branch. /d is the digit

[elasticmachine]

💚 Build Succeeded

the below badges are clickable and redirect to their specific view in the CI or DOCS

Expand to view the summary

Build stats

• Start Time: 2023-02-01T14:40:05.447+0000

• Duration: 76 min 24 sec

Test stats 🧪

Test	Results
Failed	0
Passed	7241
Skipped	746
Total	7987

💚 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 and run the E2E tests.

• /beats-tester : Run the installation tests with beats-tester.

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

[lalit-satapathy]

There is no difference in the @timestamp format before vs after?

[ritalwar]

The @timestamp field is parsed from timestamp field, the actual change is in timestamp field.

[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 rabbitmq_timestamp_filebeat_2905 upstream/rabbitmq_timestamp_filebeat_2905
git merge upstream/main
git push upstream rabbitmq_timestamp_filebeat_2905

[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 rabbitmq_timestamp_filebeat_2905 upstream/rabbitmq_timestamp_filebeat_2905
git merge upstream/main
git push upstream rabbitmq_timestamp_filebeat_2905

[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 rabbitmq_timestamp_filebeat_2905 upstream/rabbitmq_timestamp_filebeat_2905
git merge upstream/main
git push upstream rabbitmq_timestamp_filebeat_2905

[lalit-satapathy]

Looks like these messages are missing in the expected.json file, please check.

[ritalwar]

updated.