GHActions: Solaris10 is failing

[Willsparker]

Ref: #2420 #2424

As of my PR, #2405 , the GitHub action is failing, as it uses the same Vagrantfile as VPC . However, as GitHub actions don't run on a set machine, we can't install the local box that I have on the VPC machine.

The box has the SolarisStudio compiler installed on it, so we can't have it accessible by the public (I think), which rules out storing it somewhere like ci.adoptopenjdk.net/userContent/, and also rules out putting it on the Vagrant Box repository.

I'm unaware if GitHub Actions can run from a specific machine that we could pre-provision, or if they can have access to a private server to get the box from?

[Willsparker]

Linking a helpful conversation from Slack: https://adoptium.slack.com/archives/C53GHCXL4/p1641815007009500

The gist is that we should instead try to install SolarisStudio via the playbook, but have a secret provided to the box, to make it more secure; and the box will need to be re-built, without the compiler.