Update header: Add end of development banner

[larswmh]

This PR adds a banner above the header that links to the explanatory FAQ entries about the end of development of the Corona-Warn-App.

Screenshots:

Desktop EN:
coronawarn.app/en
coronawarn.app/en/faq

Desktop DE:
coronawarn.app/de
coronawarn.app/de/faq

Mobile EN:
coronawarn.app/en
coronawarn.app/en/faq

Mobile DE:
coronawarn.app/de
coronawarn.app/de/faq

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Internal Tracking ID: EXPOSUREAPP-14582

[Ein-Tim]

Looks good to me in general, one text suggestion!

[larswmh]

@MikeMcC399

You might want to use the same or similar wording as proposed in:

#ramp_down_warn

to keep the statements consistent.

The banner text was intended to be shorter so that it wouldn't take up more space than needed, especially on mobile. I'd say the wording is similar enough.

For comparison:

EN:
Banner: You still can warn other users until April 30, 2023.
FAQ #ramp_down_warn: You can still warn other CWA users about a positive test result until April 30, 2023.

DE:
Banner: Bis einschließlich 30.04.2023 können Sie andere Anwender warnen.
FAQ #ramp_down_warn: Sie können andere CWA-Nutzende noch bis einschließlich 30. April 2023 über ein positives Testergebnis informieren und diese damit warnen.

[Ein-Tim]

@larswmh / @MikeMcC399 Is both grammatically correct?

"You still can warn […]" vs. "You can still warn […]"

[MikeMcC399]

@Ein-Tim

"You still can warn […]" vs. "You can still warn […]"

Both are correct. The difference of word order causes a change in emphasis.

[larswmh]

Thanks for the reviews @MikeMcC399 & @Ein-Tim. I'm going to merge this into the update/eod branch now so it's easier for us to merge all related changes into master at once.

[MikeMcC399]

@larswmh

Will you also open a PR against update/eod now in case there are any remaining comments not covered in the individual PRs flowing into this branch?