Add headings to the security settings page (#6661)

* Changes the headings' rank of the security settings section

This commit changes the existing headings' rank of the security settings section from level 6 to level 4.

* Renames the auth.change_password string into auth.security

The "Security" preferences' section used to be called "Change password". When it was renamed, the string name wasn't changed.
This commits changes auth.change_password to auth.security.

* Adds a heading to the password change form

There was previously no heading for the part of the "Security" page that contain the password change form.
This commit adds a rank 4 heading to this section and reintroduces an "auth.change_password" string to be used inside it.

* Removes useless HR elements

The various sections of the "Security" settings page were previously separated by HR elements.
Now that there is proper headings, they're not required anymore.

* Updates CSS

This commit updates CSS in such a way that the same style is applied to all the H4 elements of the settings.

* Correct a mistake

A character went missing on one of the previous commits, broking the CSS.
This new commit fixes it.

1 files changed, 1 insertions, 1 deletions

diff --git a/app/views/auth/registrations/_sessions.html.haml b/app/views/auth/registrations/_sessions.html.haml
index 8424a8901..8586c0549 100644
--- a/app/views/auth/registrations/_sessions.html.haml
+++ b/app/views/auth/registrations/_sessions.html.haml
@@ -1,4 +1,4 @@
-%h6= t 'sessions.title'
+%h4= t 'sessions.title'
 %p.muted-hint= t 'sessions.explanation'
 
 .table-wrapper