Postgraphile v5 plugin error

### Summary

I'm trying to migrate from postgraphile v4 to v5, and I did hit an issue with the plugins.
I tried using PgSimplifyInflector and ConnectionFilter, but the same problem, which is the following:


```
Error: Error occurred when resolving preset: Error: Expected plugin, but found '[Function: PostGraphileConnectionFilterPlugin]'
Preset: {
  extends: [ { extends: [Array], plugins: [Array] } ],
  plugins: [
    [Function: PostGraphileConnectionFilterPlugin],
    <ref *1> [Function: PgSimplifyInflectorPlugin] {
      default: [Circular *1]
    } 
  ], ....
```
As a reference, I import them as following:
```
import ConnectionFilterPlugin from "postgraphile-plugin-connection-filter";
import PgSimplifyInflectorPlugin from "@graphile-contrib/pg-simplify-inflector";
```

### Additional context

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