Sort SSO providers by relevance

[bmarty]

Currently, on matrix.org, we display this:

SSO providers are not sorted by relevance, and non tech users may wonder what is GitHub?

The code is already there because it has been done on LoginFlowV2 experimentation - sorted() added here and on 1 other place too, but LoginFlowV2 is not activated yet, and will require more work.

The Quick Win is to sort also on LoginFlowV1

[bmarty]

From the link above, the order will be

            // We are on Android, so user is more likely to have a Google account
            BRAND_GOOGLE   -> 5
            // Facebook is also an important SSO provider
            BRAND_FACEBOOK -> 4
            // Twitter is more for professionals
            BRAND_TWITTER  -> 3
            // Here it's very for techie people
            BRAND_GITHUB,
            BRAND_GITLAB   -> 2
            // And finally, if the account has been created with an iPhone...
            BRAND_APPLE    -> 1
            else           -> 0