packer_ubuntu.json: update source_ami_filter

Signed-off-by: Arthur She <arthur.she@linaro.org>
Change-Id: I62057efeb9471f8b62ff54dbd4f5408cbec7abf2
1 file changed
tree: f4193f0b535c5501563053a8ffdd51fa073476f6
  1. freebsd.sh
  2. packer_freebsd.json
  3. packer_ubuntu.json
  4. ubuntu.sh