`overrideFeatureInstallOrder` gets confused when higher-priority features have dependencies

I wanted to install features in a specific order, and used `overrideFeatureInstallOrder` to do that. I was surprised when the feature I wanted to install last installed first!

I have a minimal reproduction at https://github.com/dgholz/devcontainer-install-override

In [the `devcontainer.json` file](https://github.com/dgholz/devcontainer-install-override/blob/main/.devcontainer/devcontainer.json), I have:
```
{
"image": "mcr.microsoft.com/devcontainers/base:trixie",
"features": {
"./features/use-tr": {},
"./features/remove-tr": {}
},
"overrideFeatureInstallOrder": [
"./features/use-tr",
"./features/remove-tr"
]
}
```

But `use-tr` has a dependency on the `common` feature, and `remove-tr` does not. So when `computeDependsOnInstallationOrder` runs, it gets tripped up by
https://github.com/devcontainers/cli/blob/997a2db1ec28eacfb718d07e7741dbd57af59564/src/spec-configuration/containerFeaturesOrder.ts#L625
`use-tr` gets excluded, and `remove-tr` has round priority `1` so gets installed before `common` (which has round priority `0`)

The fix is to either set the round priority transitively (so `common` would get round priority `2` from `use-tr`); or to reverse the calculated priority ordering, so features with no dependencies would be installed first.