Fixing logic error when executable present in package

[twerthi]

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Background

User reported that when executable is present in the package, the code searches for grate.dll and fails when it cannot be found.

Results

Fixed logic flaw for the code path version checking.

Before

If statement was incorrectly comparing null to a specified version and dropping into a condition where it looks for .dll and not an .exe or Linux executable.

After

If condition now checks to make sure the variable isn't null first before attempting to compare. Now correctly follows the code path to search for the OS executable.

Pre-requisites

• Id should be a GUID that is not 00000000-0000-0000-0000-000000000000
  • NOTE If you are modifying an existing step template, please make sure that you do not modify the Id property (updating the Id will break the Library sync functionality in Octopus).
• Version should be incremented, otherwise the integration with Octopus won't update the step template correctly
• $Meta must have ExportedAt and OctopusVersion updated
• Parameter names should not start with $
• Step template parameter names (the ones declared in the JSON, not the script body) should be prefixed with a namespace so that they are less likely to clash with other user-defined variables in Octopus (see this issue). For example, use an abbreviated name of the step template or the category of the step template).
• LastModifiedBy field must be present, and (optionally) updated with the correct author
• The best practices documented here have been applied
• If a new Category has been created:
  • An image with the name {categoryname}.png must be present under the step-templates/logos folder
  • The switch in the humanize function in gulpfile.babel.js must have a case statement corresponding to it

Fixes #1642

[github-actions]

Review this PR in Hyponome for a side-by-side diff of the step-template JSON and any embedded scripts.