Rename and rework "Getting Started" walkthrough to "Create an Ansible Environment"

[alisonlhart]

The existing Getting Started walkthrough was designed to serve a temporary role as the primary Ansible extension walkthrough.

Since we're now creating more granular and focused walkthrough, this walkthrough is being split into two - "Create an Ansible Environment" and "Start automating with your first Ansible playbook" (coming soon).

Details:

• Walkthrough renamed from "Getting Started with Ansible Extension" to "Create an Ansible environment"
• Removed steps for resources and settings, since these features are/will be covered elsewhere
• Added new image for "Install the Ansible environment package" step
• Add images to the .vscodeignore exceptions, where other walkthrough images are included

These changes align this walkthrough with the "Create an Ansible environment" walkthrough designed by the UX team.

See AAP-27799.

[alisonlhart]

Still need to add UI test.