[ESET Protect] Remove BOM from the Syslog message

[moxarth-rathod]

Proposed commit message

eset_protect: syslog message prefix breaks event ingestion pipeline 
In the official documentation [1], they've mentioned a note regarding the
Syslog server supporting a UTF-8 BOM encoding. This PR fixes the ingestion
pipeline by adding a `dissect` processor to remove the BOM prefix from the 
syslog messages, so that the pipeline does not fail in case of the presence
of this prefix in the events.  
[1]https://help.eset.com/protect_cloud/en-US/admin_server_settings_export_to_syslog.html

Checklist

• I have reviewed tips for building integrations and this pull request is aligned with them.
• I have verified that all data streams collect metrics or logs.
• I have added an entry to my package's changelog.yml file.
• I have verified that Kibana version constraints are current according to guidelines.
• I have verified that any added dashboard complies with Kibana's Dashboard good practices

How to test this PR locally

• Clone integrations repo.
• Install elastic package locally.
• Start elastic stack using elastic-package.
• Move to integrations/packages/eset_protect directory.
• Run the following command to run tests.

elastic-package test

Related issues

• Closes [ESET PROTECT]: Syslog message prefix breaks event ingestion pipeline #13442

[elasticmachine]

Pinging @elastic/security-service-integrations (Team:Security-Service Integrations)

[elastic-vault-github-plugin-prod]

🚀 Benchmarks report

To see the full report comment with /test benchmark fullreport

[ShourieG]

LGTM

[elastic-sonarqube]

Quality Gate passed

Issues
0 New issues
0 Fixed issues
0 Accepted issues

Measures
0 Security Hotspots
100.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube

[elasticmachine]

💚 Build Succeeded

• Buildkite Build
• Commit: 3fbdcd1

History

• 💚 Build #24974 succeeded d876ed1
• 💚 Build #24924 succeeded 05e2f81
• 💔 Build #24923 failed 7626ad8

cc @moxarth-rathod

[elastic-vault-github-plugin-prod]

Package eset_protect - 1.7.1 containing this change is available at https://epr.elastic.co/package/eset_protect/1.7.1/