Add support for comments in version files like .nvmrc

I recently came across a project with a `.nvmrc` file with a comment in it which is useful to tell maintainers that unfortunately it's not the single source of truth (due to it being duplicated in a `pom.xml` that uses frontend-maven-plugin). Could support be added to ignore anything after a version number that comes at the start of the file?

`cat .nvmrc`
`12.18.0`
`# note to update the pom.xml node version too`

Start by locating the code that reads version files such as .nvmrc, then check how a leading version followed by a comment is currently handled. Add coverage for the shown .nvmrc content and confirm that the version is read while the comment is ignored.

Written by the indexing model from the issue text.