Merge branch 'minac_do_not_check_first_line_for_each_line' into 'master'

Do not check skip condition for each CSV line

See merge request https://gitlab.com/gitlab-org/gitlab/-/merge_requests/157912



Merged-by: Terri Chu <tchu@gitlab.com>
Approved-by: Marc Saleiko <msaleiko@gitlab.com>
Approved-by: Terri Chu <tchu@gitlab.com>
Reviewed-by: Marc Saleiko <msaleiko@gitlab.com>
Co-authored-by: Mehmet Emin INAC <minac@gitlab.com>

ee/app/services/vulnerability_exports/export_service.rb

@@ -66,13 +66,9 @@ def finalise_segmented_export
 
       vulnerability_export.export_parts.each do |part|
         part.file.open do |stream|
-          first_skip = export_header.present?
-          stream.each_line do |line|
-            if first_skip
-              first_skip = false
-              next
-            end
+          stream.readline if export_header.present? # Moves the cursor to next line
 
+          stream.each_line do |line|
             # The encoding of the parts is read as ASCI-8BIT.
             # We need to force the encoding to utf-8 to avoid a write failure due to
             # wide-chars used in place like group names.