remove the logo_image from block / cover

[flynnduism]

Removes a glitch where the Docsy template + shortcode for rendering the landing page is adding an inline image.

This PR modifies the cover block partial template: https://github.com/google/docsy/blob/main/layouts/shortcodes/blocks/cover.html#L38C9-L38C324

{{ with .Get "title" }}<h1 class="display-1 mt-0 mt-md-5 pb-4">{{ $title := . }}{{ with $logo_image }}{{ $logo_image_resized := (.Fit (printf "70x70 %s" $logo_anchor)) }}<img class="td-cover-logo" src="{{ $logo_image_resized.RelPermalink }}" alt="{{ $title | html }} Logo">{{ end }}{{ $title | html }}</h1>{{ end }}

to remove the inline {{ with $logo_image }} part