Update the Ansible pin

This updates the Ansible pin used in our Packer projects to match the
version pin used in our Ansible role projects.

requirements.txt

@@ -12,7 +12,7 @@
 # jumping to another major version without testing, since there are
 # often breaking changes across major versions.  This is the reason
 # for the upper bound.
-ansible>=8,<10
+ansible>=9,<10
 # ansible-core 2.16.3 through 2.16.6 suffer from the bug discussed in
 # ansible/ansible#82702, which breaks any symlinked files in vars,
 # tasks, etc. for any Ansible role installed via ansible-galaxy.