Avoid resolving paths on fragments (#357)

Fixes an issue where modules with fragment paths are resolved against the URI path.

pkl-doc/src/main/kotlin/org/pkl/doc/DocPackageInfo.kt

@@ -161,7 +161,7 @@ data class DocPackageInfo(
       "pkl:/" -> "pkl:${moduleName.substring(4)}".toUri()
       else -> {
         val path = getModulePath(moduleName, moduleNamePrefix).uriEncoded + ".pkl"
-        URI(importUri).resolve(path)
+        URI(importUri + path)
       }
     }