Breaking: #96835 - https as default scheme in PageRouter 

See forge#96835

Description 

The fallback scheme in \TYPO3\CMS\Core\Routing\PageRouter::generateUri() is set to https instead of http when linking to other pages.

Impact 

If the site configuration does not provide a scheme but only a domain (e.g. www.domain.tld), the scheme is set to https.

Affected Installations 

All installations which use a site configuration without providing a scheme and which must not be delivered through https.

Migration 

If https can't be used, the entry point must define the scheme, e.g. http://www.domain.tld.