Use git follow flag for commits page when retrieve history for file or directory

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

CHANGELOG

@@ -9,6 +9,7 @@ v 8.2.0 (unreleased)
   - Allow users to select the Files view as default project view (Cristian Bica)
   - Show "Empty Repository Page" for repository without branches (Artem V. Navrotskiy)
   - Fix: Inability to reply to code comments in the MR view, if the MR comes from a fork
+  - Use git follow flag for commits page when retrieve history for file or directory
 v 8.1.0
   - Ensure MySQL CI limits DB migrations occur after the fields have been created (Stan Hu)

app/models/repository.rb

@@ -67,13 +67,16 @@ class Repository
   end
   def commits(ref, path = nil, limit = nil, offset = nil, skip_merges = false)
-    commits = Gitlab::Git::Commit.where(
+    options = {
       repo: raw_repository,
       ref: ref,
       path: path,
       limit: limit,
       offset: offset,
-    )
+    }
+
+    options[:follow] = true if path.present?
+    commits = Gitlab::Git::Commit.where(options)
     commits = Commit.decorate(commits, @project) if commits.present?
     commits
   end