Fix using --javaexecutable in Linux

[Sickafant]

There is a restriction on --javaexecutable usage for platforms other than Windows, due to logic checking for usage of '.exe'. To allow other platforms to specify their java executable and skip the version detection the way Windows can, adjust the condition for the version check.

Exposes an easy workaround for #18

Proposed Changes

1. Use of --javaexecutable to bypass the version detection is possible with windows, but not in platforms where java binary is not named java.exe. Adjust the conditions so that version detection and autodownload can be skipped when a user passes in an explicit java binary they want to use.
2. Ultimately want to be able to use this change with npm-groovy-lint

Readiness Checklist

Author/Contributor

• Add entry to the CHANGELOG.md listing the change and linking to the corresponding issue (if appropriate)
• If documentation is needed for this change, has that been included in this pull request

Reviewing Maintainer

• Label as breaking if this is a large fundamental change
• Label as either automation, bug, documentation, enhancement, infrastructure, or performance

[nvuillam]

Great, thanks for your update :)
I'll manage the dependency issue before releasing a new version

[nvuillam]

@Sickafant v2.6.0 has been released :)