Readme/example fix

[samcrudge]

what

• Describe high-level what changed as a result of these commits (i.e. in plain-english, what do these changes mean?)
• Example of 'Origin Group with the origin created by this module as a primary origin and an additional
  S3 bucket as a failover origin' showed the s3_origins & origin_group as a map(any) rather than a list(map) causing builds to fail when using said example.

why

• Provide the justifications for the changes (e.g. business case).
• Describe why these changes were made (e.g. why do these commits fix the problem?)
• Examples that reflect the required schema.

references

• Link to any supporting github issues or helpful documentation to add some context (e.g. stackoverflow).
• README.md & README.yaml

[joe-niland]

@samcrudge apologies that this was missed - did you want to merge in the main branch so we can get this one merged?

[samcrudge]

Il do that today

[samcrudge]

@joe-niland I've synced the branches. do you need me to run any commands?

[joe-niland]

/terratest

[joe-niland]

Thanks for your contribution @samcrudge !