Remove support for disable_jump_reply user setting (#7359)

test/javascripts/fixtures/session-fixtures.js.es6

@@ -23,7 +23,6 @@ export default {
       can_edit: true,
       can_invite_to_forum: true,
       should_be_redirected_to_top: false,
-      disable_jump_reply: false,
       custom_fields: {},
       muted_category_ids: [],
       dismissed_banner_key: null,

test/javascripts/fixtures/user_fixtures.js.es6

@@ -182,7 +182,6 @@ export default {
       watched_category_ids: [3],
       watched_first_post_category_ids: [],
       private_messages_stats: { all: 101, mine: 13, unread: 3 },
-      disable_jump_reply: false,
       gravatar_avatar_upload_id: 5275,
       custom_avatar_upload_id: 1573,
       card_image_badge: "/images/avatar.png",
@@ -2514,7 +2513,6 @@ export default {
         external_links_in_new_tab: false,
         dynamic_favicon: false,
         enable_quoting: true,
-        disable_jump_reply: false,
         digest_after_minutes: 10080,
         automatically_unpin_topics: true,
         auto_track_topics_after_msecs: 240000,