5.1.2v1 for Joomla! 5.1.2

A short general information on the naming of files:

New German Joomla! Installations:

Joomla_0.0.0-Stable-Full_Package_German.[zip|tar.gz|tar.bz2]

Add German Language to existing Joomla! Installations:

de-[AT|CH|DE|LI|LU]_joomla_lang_full_0.0.0v[1|2|...].zip

What's Changed

• Fix message published/unpublished item- it is for 1 artilce by @chmst in #3200
• [a11y] Fix missing aria-label in pagenavigation #3202 by @zero-24 in #3203
• [4.1] Improve German translation for COM_FINDER_QUERY_RESULTS #2542 by @zero-24 in #3205
• [4.x/5.x] Falsche Übersetzung skip-to navigation by @tecpromotion in #3209
• [4.4] Standardisation of the iFrame spelling by @tecpromotion in #3215
• [5.1] Allow PDF embeding again by @tecpromotion in #3213
• [5.1] Add update channel reset to Joomla Update Component by @tecpromotion in #3218

Full Changelog: 5.1.1v1...5.1.2v1
Milestone 5.1.2v1: https://github.com/joomlagerman/joomla/milestone/140?closed=1