Fix mixed-content error of loading http over https scheme after disconnection from social account

[kola-er]

The three possible sources of redirect-uri to backend.strategy.redirect() call would most likely supply a relative uri. From my encounter with this, the redirect-uri got loaded over http which caused Mixed-content error since the social platform disconnection request was made over https scheme.

So passing any of the relative redirect-uri to backend.strategy.absolute_uri() would pass the absolute redirect-uri with the desired scheme to backend.strategy.redirect().

[omab]

Thanks!