Remove caching of Maven metadata

[TheEadie]

Description

On self-hosted runners the data would be cached on first run and never updated. This leads to setup-flyway never discovering new versions of Flyway to install unless the agent is rebuilt.

There is a risk that this introduces more traffic to download.red-gate.com

Related issue

None

Check list

• Mark if documentation changes are required.
• Mark if tests were added or updated to cover the changes.

[DoodleBobBuffPants]

If we want to minimize traffic, maybe the flow ought to be:

• If version is cached, use it
• If version is in cached metadata file, use that file
• Otherwise, fetch and cache metadata file

[TheEadie]

I'm not sure the traffic risk is worth the overhead of the code to be honest. In the worst case each job runs on an ephemeral agent and its a cache miss everytime.