Set versions for new Flutter capabilities

```ts
// TODO: Fix these versions.
get supportsForceWsVmService() { return versionIsAtLeast(this.version, "1.8.0"); }
get supportsExposeUrl() { return versionIsAtLeast(this.version, "1.8.0"); }
```

These need fixing after the Flutter changes are merged (and updating if there are any changes in the PR) to ensure we don't try to send them to versions of Flutter that don't support them.