Fix unnecesary import for uri method use

I need to import `ParseException` to use the uri method:
```scala
scala> import org.http4s.Uri
import org.http4s.Uri

scala> val githubHome = Uri.uri("https://github.com")
<console>:8: error: not found: type ParseException
       val githubHome = Uri.uri("https://github.com")
                               ^

scala> import org.http4s.ParseException
import org.http4s.ParseException

scala> val githubHome = Uri.uri("https://github.com")
githubHome: org.http4s.Uri = https://github.com
```

But the macro construction of the literal uri is an internal design, and `ParseException` it's not used directly in this case.