Remove Subscribe for Newsletter option in Settings page

[Oanh-and-only-Oanh]

Remove the newsletter subscribe switch in the settings for members since we are not doing the Weekly Newsletters anymore.

[SathyaJayabal]

@kkartunov @Oanh-and-only-Oanh , since newsletter preferences were the only section present under email preferences, now the email tab is empty. We should remove the email tab too as it is not a good UX to have an empty tab.

[kkartunov]

@SathyaJayabal we need to keep it because of:

1. All other tabs are external and load in new page thus can't begin with new one which breaks tabs.
2. We could add email preferences for general newsletter latter in this section.

Please, feel free to proceed with this one.

[SathyaJayabal]

@kkartunov , marking this as pass as per comment above.

[Jobee1]

Tested in Beta environment: Only E-mail Preferences is displayed.