Standardize page-title bottom margin styling

Removes unnecessary and problematic bottom margin 0 from last-child

app/assets/javascripts/issuable_create/components/issuable_create_root.vue

@@ -29,7 +29,7 @@ export default {
 <template>
   <div class="issuable-create-container">
     <slot name="title"></slot>
-    <hr />
+    <hr class="gl-mt-0" />
     <issuable-form
       :description-preview-path="descriptionPreviewPath"
       :description-help-path="descriptionHelpPath"

app/assets/stylesheets/framework/typography.scss

@@ -573,10 +573,6 @@ body {
   font-size: 1.25em;
   font-weight: $gl-font-weight-bold;
 
-  &:last-child {
-    margin-bottom: 0;
-  }
-
   &.with-button {
     line-height: 34px;
   }

app/assets/stylesheets/pages/editor.scss

@@ -216,10 +216,6 @@
   }
 }
 
-.editor-title-row {
-  margin-bottom: 20px;
-}
-
 .popover.suggest-gitlab-ci-yml {
   z-index: $header-zindex - 1;
 }

app/views/projects/blob/edit.html.haml

@@ -9,9 +9,8 @@
       = link_to "the file", project_blob_path(@project, tree_join(@branch_name, @file_path)), target: "_blank", rel: 'noopener noreferrer', class: 'gl-link'
       and make sure your changes will not unintentionally remove theirs.
 
-.editor-title-row
-  %h3.page-title.blob-edit-page-title
-    Edit file
+%h3.page-title.blob-edit-page-title
+  Edit file
 .file-editor
   %ul.nav-links.no-bottom.js-edit-mode.nav.nav-tabs
     %li.active

app/views/projects/blob/new.html.haml

 - breadcrumb_title _("Repository")
 - page_title _("New File"), @path.presence, @ref
 
-.editor-title-row
-  %h3.page-title.blob-new-page-title
-    New file
+%h3.page-title.blob-new-page-title
+  New file
 .file-editor
   = form_tag(project_create_blob_path(@project, @id), method: :post, class: 'js-edit-blob-form js-new-blob-form js-quick-submit js-requires-input', data: blob_editor_paths(@project)) do
     = render 'projects/blob/editor', ref: @ref

changelogs/unreleased/standardize-page-title-bottom-margin-styling.yml

+---
+title: 'Remove last-child bottom-margin: 0 from page-title class'
+merge_request: 49884
+author:
+type: fixed

ee/app/assets/javascripts/iterations/components/iteration_form.vue

@@ -145,7 +145,7 @@ export default {
         {{ isEditing ? __('Edit iteration') : __('New iteration') }}
       </h3>
     </div>
-    <hr />
+    <hr class="gl-mt-0" />
     <gl-form class="row common-note-form">
       <div class="col-md-6">
         <div class="form-group row">

ee/app/views/admin/geo/nodes/index.html.haml

@@ -5,7 +5,7 @@
 = render partial: 'admin/geo/shared/license_alert'
 
 .d-flex.align-items-center.border-bottom.border-default.mb-4
-  %h3{ :class => "page-title gl-mb-5!" }
+  %h3{ :class => "page-title" }
     = _("Geo Nodes")
   - if @nodes.any?
     = link_to s_("GeoNodes|New node"), new_admin_geo_node_path, class: 'gl-button btn btn-success ml-auto qa-new-node-link'