Fix button style inconsistencies in blob/breadcrumb

Thankfully it looks like we can just add missing gl-button
classes to the other buttons in this partial.

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

@@ -23,13 +23,13 @@
     - if blob.readable_text?
       - if blame
         = link_to 'Normal view', project_blob_path(@project, @id),
-            class: 'btn'
+            class: 'gl-button btn'
       - else
         = link_to 'Blame', project_blame_path(@project, @id),
             class: 'gl-button btn js-blob-blame-link' unless blob.empty?
 
     = link_to 'History', project_commits_path(@project, @id),
-        class: 'btn'
+        class: 'gl-button btn'
 
     = link_to 'Permalink', project_blob_path(@project,
         tree_join(@commit.sha, @path)), class: 'gl-button btn js-data-file-blob-permalink-url'

changelogs/unreleased/281571-fix-blob-header-button-styles.yml

+---
+title: Update button styles in blob header
+merge_request: 47571
+author:
+type: other