Add support to MAAS+TLS

[Pedro Guimarães]

MAAS 3.2 has now support for TLS natively.

However, when trying to use a MAAS+TLS with Juju 2.9.33, I get the following error stack at bootstrap.

ERROR Forbidden
23:25:53 DEBUG cmd supercommand.go:537 error stack:
ServerError: 401 Unauthorized (Forbidden)
github.com/juju/gomaasapi/v2.Client.dispatchSingleRequest:129:
github.com/juju/gomaasapi/v2.(*controller)._getRaw:887:
github.com/juju/gomaasapi/v2.(*controller)._get:863:
github.com/juju/gomaasapi/v2.(*controller).checkCreds:766: Forbidden
github.com/juju/gomaasapi/v2.newControllerWithVersion:107:
github.com/juju/gomaasapi/v2.newControllerUnknownVersion:125:
github.com/juju/juju/provider/maas.(*maasEnviron).SetCloudSpec:323:
github.com/juju/juju/provider/maas.NewEnviron:140:
github.com/juju/juju/environs/bootstrap.PrepareController:131:
github.com/juju/juju/cmd/juju/commands.(*bootstrapCommand).Run:790:

If I disable TLS, the credentials work fine for bootstrap. I've also added the CA chain to the juju client machine.

[Pedro Guimarães (pguimaraes)]

There are two alternatives:
1) Adding the ca chain via cloud-init to the juju controller and directly to the node running juju client
2) Setting the ca chain in the ~/.local/share/juju/clouds.yaml, under the "ca-certificates" field

Setting this bug as invalid.