Update syntax-highlight to latest version

Julien LepillerTue Aug 24 23:16:23+0200 2021

73e93db

gitile/assets
namelast commitdate
css/Dark theme and improved markdown styleTue Aug 10 14:45:45+0200 2021
images/License with reuse.software, code is under AGPL, not LGPLSun Mar 21 18:00:42+0100 2021
js/License with reuse.software, code is under AGPL, not LGPLSun Mar 21 18:00:42+0100 2021