Social media icons should have a label title for the screenreader

[bit-pro-iew-eui]

• [x] Social media icons should have a label "Social Media" only for the screenreader, not visible.

https://swiss.github.io/styleguide/de/footer.html#04-footer-02-social-media

• [x] Please add a label also for "Social Media Sharing"

https://swiss.github.io/styleguide/de/functions.html#04-functions-02-social-sharing

[gillerr]

Simply add a label with sr-only class to the nav element

[bit-pro-iew-eui]

Please don't use H1-6 use another html-tag which is read by at least NVDA