Remove stale link to jar-to-war getting started guide

[IMWoo94]

Version : Spring Boot 3.3.4 Reference Doc.

Changed the Not Found link provided in the Reference Doc to a link covering the Build Plugin.

The reference Doc already provides a direct content to Jar and War. I think it would create better synergy if you provided a link to the Build Tool rather than providing a removed guide.

Reference Doc : https://docs.spring.io/spring-boot/how-to/deployment/traditional-deployment.html#howto.traditional-deployment.convert-existing-application

Not Found Link : Getting Started Guide on Converting a jar to a war.

Suggest Link : Build Tool Plugins

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[snicoll]

Thanks for the PR.

The guide has been dropped so this looks like an oversight, see #42110

[IMWoo94]

Thank you for finding the issue

The current PR provides a new link, but can I delete it and rewrite it with the code that's been removed?

[philwebb]

Thanks for the PR. I don't think we should reproduce the code from the old guide, but we should update the link when we merge this. It should be xref:build-tool-plugin:index.adoc[]

[IMWoo94]

Update can be carried out in two ways.

1. "See the Getting Started Guide on Converting a jar to a war." comment delete

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2. Modify links using xref:build-tool-plugin:index.adoc[]

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#42110 and the comments
Number 2 provides the same link using xref:build-tool-plugin:index.adoc[] at the top.
This is overlapping, and I think option 2 is ambiguous because it is located not far away.

I think option 1 is correct so current PR option 1 apply.
Which of the two options do you think is more correct?

[philwebb]

Thanks @IMWoo94