Use flex layout instead of data-equalizer in feeds

Using data-equalizer is always hard due to the JavaScript it uses, while
the flex layout works all the time.

app/assets/stylesheets/widgets/feeds/participation.scss

@@ -1,20 +1,30 @@
 .feeds-participation {
 
+  @include breakpoint(medium) {
+    display: flex;
+
+    .feed-proposals:not(:only-child) {
+      width: 2 * 100% / 3;
+    }
+
+    .feed-debates:not(:only-child) {
+      width: 1 * 100% / 3;
+    }
+
+    .feed-proposals,
+    .feed-debates {
+      display: flex;
+      flex-direction: column;
+
+      .feed-content {
+        flex: 1;
+      }
+    }
+  }
+
   .feed-debates,
   .feed-proposals {
     @include grid-col;
     margin-top: $line-height;
   }
-
-  .feed-proposals:not(:only-child) {
-    @include breakpoint(medium) {
-      width: 2 * 100% / 3;
-    }
-  }
-
-  .feed-debates:not(:only-child) {
-    @include breakpoint(medium) {
-      width: 1 * 100% / 3;
-    }
-  }
 }

app/components/widgets/feeds/debates_component.html.erb

@@ -1,5 +1,5 @@
 <div id="feed_debates" class="feed-debates">
-  <div class="feed-content" data-equalizer-watch>
+  <div class="feed-content">
     <h3 class="title"><%= t("welcome.feed.most_active.#{feed.kind}") %></h3>
 
     <% feed.items.each do |item| %>

app/components/widgets/feeds/participation_component.html.erb

@@ -1,4 +1,4 @@
-<div class="row margin-bottom feeds-list feeds-participation" data-equalizer data-equalize-on="medium">
+<div class="row margin-bottom feeds-list feeds-participation">
   <% feeds.each do |feed| %>
     <% if feed_proposals?(feed) %>
       <%= render Widgets::Feeds::ProposalsComponent.new(feed) %>

app/components/widgets/feeds/proposals_component.html.erb

@@ -1,5 +1,5 @@
 <div id="feed_proposals" class="feed-proposals">
-  <div class="feed-content" data-equalizer-watch>
+  <div class="feed-content">
     <h3 class="title"><%= t("welcome.feed.most_active.#{feed.kind}") %></h3>
 
     <% feed.items.each do |item| %>