HAMLLint: Fix `HtmlAttributes` offences

app/views/layouts/devise_mailer.html.haml

 !!! 5
 %html
   %head
-    %meta(content='text/html; charset=UTF-8' http-equiv='Content-Type')
+    %meta{ content: 'text/html; charset=UTF-8', 'http-equiv'=> 'Content-Type' }
     = stylesheet_link_tag 'mailers/devise'
 
   %body

app/views/projects/branches/_branch.html.haml

@@ -4,7 +4,7 @@
 - number_commits_behind = diverging_commit_counts[:behind]
 - number_commits_ahead = diverging_commit_counts[:ahead]
 - merge_project = can?(current_user, :create_merge_request, @project) ? @project : (current_user && current_user.fork_of(@project))
-%li(class="js-branch-#{branch.name}")
+%li{ class: "js-branch-#{branch.name}" }
   %div
     = link_to namespace_project_tree_path(@project.namespace, @project, branch.name), class: 'item-title str-truncated' do
       = branch.name
@@ -12,7 +12,7 @@
     - if branch.name == @repository.root_ref
       %span.label.label-primary default
     - elsif @repository.merged_to_root_ref? branch.name
-      %span.label.label-info.has-tooltip(title="Merged into #{@repository.root_ref}")
+      %span.label.label-info.has-tooltip{ title: "Merged into #{@repository.root_ref}" }
         merged
 
     - if @project.protected_branch? branch.name

app/views/sherlock/queries/show.html.haml

@@ -3,10 +3,10 @@
 
 %ul.nav-links
   %li.active
-    %a(href="#tab-general" data-toggle="tab")
+    %a{ href: "#tab-general", data: { toggle: "tab" } }
       = t('sherlock.general')
   %li
-    %a(href="#tab-backtrace" data-toggle="tab")
+    %a{ href: "#tab-backtrace", data: { toggle: "tab" } }
       = t('sherlock.backtrace')
 
 .row-content-block

app/views/sherlock/transactions/show.html.haml

@@ -3,15 +3,15 @@
 
 %ul.nav-links
   %li.active
-    %a(href="#tab-general" data-toggle="tab")
+    %a{ href: "#tab-general", data: { toggle: "tab" } }
       = t('sherlock.general')
   %li
-    %a(href="#tab-queries" data-toggle="tab")
+    %a{ href: "#tab-queries", data: { toggle: "tab" } }
       = t('sherlock.queries')
       %span.badge
         #{@transaction.queries.length}
   %li
-    %a(href="#tab-file-samples" data-toggle="tab")
+    %a{ href: "#tab-file-samples", data: { toggle: "tab" } }
       = t('sherlock.file_samples')
       %span.badge
         #{@transaction.file_samples.length}