[Tech Debt] Update `js-yaml` dependency to >= 4

[kavilla]

js-yaml is a JavaScript library that allows developers to parse and serialize YAML (YAML Ain't Markup Language) data in their JavaScript projects. YAML is a human-readable data serialization format that is often used for configuration files, data exchange between systems, and other tasks where data needs to be easily readable by humans.

Current dependency: "js-yaml": "^3.14.0"

Note: Upgrading this dependency might incur breaking changes or none in the usage. When upgrading please be aware of these issues.

• Upgrade js-yaml and handle required usage changes from osd-apm-config-loader package
  • Research in usage of osd/apm-config-loader
  • Can this be removed?
• Upgrade js-yaml and handle required usage changes from osd-config package
• Upgrade js-yaml and handle required usage changes from osd-optimizer package

[andreymyssak]

I can't say with certainty whether it is used for something or not. At the moment, only one file imports it - src/apm.js, and I couldn't find any use for src/apm.js.

To save some of your time I'll leave the links below, maybe they can provide some clarity for you

1. Add the @kbn/apm-config-loader package
2. Instrument Kibana with Elastic APM
3. Instrument Kibana with APM RUM agent