Commit c9e1551 changed file mode to binary from text. When on binary,
Python does not apply newlines so the resulting file has no line
terminator. This has not been an issue up to HAProxy version 1.8, but
testing on HAProxy 2.2.2 fails configuration check.
Workaround this HAProxy issue by adding a line terminator to the
certificate list file.
Task: 40593
Story: 2007974
Change-Id: Iedd22e75a9124a41b776305f2fcb0caaabd07d6a