Fixes in various spotlights and spotlight template

To make things a bit easier to migrate the spotlights to the RSD, I would like to change the example code block in the CFF spotlight.

It used to use jekyll syntax with {% highlight yaml %}. This MR asks to exchange this with markdown ``` blocks.

There are some slight changes, i.e. line numbers are shown now, and the code block has full width. This is how it looks now:

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