Pipe `--json` to `jq` for `packages` sub-command

I was trying to do something like this:

```shell
dbt-autofix deprecations --json | jq .
```

which worked:

```
Warning: Path /Users/dbeatty/jaffle-minis/minis/010a2_autofix_packages/seeds does not exist
Warning: Path /Users/dbeatty/jaffle-minis/minis/010a2_autofix_packages/macros does not exist
Warning: Path /Users/dbeatty/jaffle-minis/minis/010a2_autofix_packages/tests does not exist
Warning: Path /Users/dbeatty/jaffle-minis/minis/010a2_autofix_packages/analyses does not exist
Warning: Path /Users/dbeatty/jaffle-minis/minis/010a2_autofix_packages/snapshots does not exist
{
"mode": "complete"
}
```

But this didn't:

```shell
dbt-autofix packages --force-upgrade --json | jq .
```

```
jq: parse error: Invalid numeric literal at line 1, column 12
```