Jack in fails to inject zprint dependency

If I set `calva.prettyPrintingOptions.printEngine = "zprint"`, the dependency is not injected when I jack in.

```
Error printing return value (FileNotFoundException) at clojure.lang.RT/load (RT.java:482).
Could not locate zprint/core__init.class, zprint/core.clj or zprint/core.cljc on classpath.
```

Works as expected if I add the dependency to the project deps or an alias.