settings: Remove user-name-section from email input.
settings: Remove user-name-section from email input.

We handle the css using email-change-form and thus
there is no need for 'user-name-section' class as
this element is used for emails and not user names.

andersk/zulip,eeshangarg/zulip,kou/zulip,kou/zulip,eeshangarg/zulip,andersk/zulip,andersk/zulip,rht/zulip,eeshangarg/zulip,kou/zulip,punchagan/zulip,kou/zulip,hackerkid/zulip,zulip/zulip,rht/zulip,zulip/zulip,kou/zulip,hackerkid/zulip,rht/zulip,eeshangarg/zulip,rht/zulip,hackerkid/zulip,zulip/zulip,zulip/zulip,hackerkid/zulip,hackerkid/zulip,zulip/zulip,hackerkid/zulip,punchagan/zulip,eeshangarg/zulip,punchagan/zulip,punchagan/zulip,rht/zulip,kou/zulip,andersk/zulip,zulip/zulip,punchagan/zulip,kou/zulip,andersk/zulip,andersk/zulip,rht/zulip,eeshangarg/zulip,hackerkid/zulip,andersk/zulip,punchagan/zulip,punchagan/zulip,zulip/zulip,eeshangarg/zulip,rht/zulip