Build fails when contributors not present

[h-enk]

Description

Describe the issue that you're seeing.

Build fails, when contributors: [] is not present in the frontmatter of blog pages.

Update layouts/partials/main/blog-meta.html (line 1) to allow for absence of contributors: []:

{{ $last := sub (len .Params.contributors) 1 -}}

Steps to reproduce

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thuliteio/doks#1279

Expected result

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Actual result

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Environment

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