Use semver latest for sitemaps

[recrwplay]

Updates antora-modify-sitemaps so that any releases that are determined to be prereleases according to semver rules are ignored when the extension is determining which component version should be considered as the 'latest' or 'current' version for the purpose of generating a sitemap.

• Uses the semver package to determine if a version is a prerelease. Most of our projects do not publish preview content without marking it as prerelease in Antora, but those that do typically append -preview to a version number. These versions are considered prerelase by semver's rules, and will be excluded by default when deciding what version a sitemap should be generated from
• To generate a sitemap from a preview version you now need to specify the component and version using the data attribute as documented in the readme file. This version will override the default if the extension is registered twice, which can happen when the extension is required by the playbook but also from the Antora CLI by using the --extension arg.

[neo-technology-commit-status-publisher]

Thanks for the documentation updates.

The preview documentation has now been torn down - reopening this PR will republish it.