HAMLLint: Fix `UnnecessaryStringOutput` offences

app/views/projects/deployments/_deployment.html.haml

 %tr.deployment
   %td
-    %strong= "##{deployment.iid}"
+    %strong= ("##{deployment.iid}")
   %td
     = render 'projects/deployments/commit', deployment: deployment
@@ -8,7 +8,7 @@
   %td.build-column
     - if deployment.deployable
       = link_to [@project.namespace.becomes(Namespace), @project, deployment.deployable], class: 'build-link' do
-        = "#{deployment.deployable.name} (##{deployment.deployable.id})"
+        = ("#{deployment.deployable.name} (##{deployment.deployable.id})")
       - if deployment.user
         by
         = user_avatar(user: deployment.user, size: 20)

app/views/projects/diffs/_file_header.html.haml

@@ -25,4 +25,4 @@
   - if diff_file.mode_changed?
     %small
-      = "#{diff_file.a_mode} → #{diff_file.b_mode}"
+      #{diff_file.a_mode} → #{diff_file.b_mode}

app/views/projects/forks/index.html.haml

 .top-area
   .nav-text
     - full_count_title = "#{@public_forks_count} public and #{@private_forks_count} private"
-    = "#{pluralize(@total_forks_count, 'fork')}: #{full_count_title}"
+    #{pluralize(@total_forks_count, 'fork')}: #{full_count_title}
   .nav-controls
     = form_tag request.original_url, method: :get, class: 'project-filter-form', id: 'project-filter-form' do |f|

app/views/projects/services/mattermost_slash_commands/_installation_info.html.haml

@@ -4,4 +4,4 @@
       .col-sm-9.col-sm-offset-3
         = link_to new_namespace_project_mattermost_path(@project.namespace, @project), class: 'btn btn-lg' do
           = custom_icon('mattermost_logo', size: 15)
-          = 'Add to Mattermost'
+          Add to Mattermost

app/views/shared/tokens/_scopes_form.html.haml

@@ -5,5 +5,5 @@
 - scopes.each do |scope|
   %fieldset
     = check_box_tag "#{prefix}[scopes][]", scope, token.scopes.include?(scope), id: "#{prefix}_scopes_#{scope}"
-    = label_tag "#{prefix}_scopes_#{scope}", scope
-    %span= "(#{t(scope, scope: [:doorkeeper, :scopes])})"
+    = label_tag ("#{prefix}_scopes_#{scope}"), scope
+    %span= t(scope, scope: [:doorkeeper, :scopes])