docs(website): Fix-up a package curation example

The `source_code_origins` property is an array. This is a fix-up of
433778b.

Signed-off-by: Frank Viernau <frank_viernau@epam.com>

website/docs/configuration/package-curations.md

@@ -83,7 +83,7 @@ A curation file consists of one or more `id` entries:
       path: "subdirectory"
     is_metadata_only: true
     is_modified: true
-    source_code_origins: "ARTIFACT, VCS"
+    source_code_origins: [ARTIFACT, VCS]
 ```
 
 Where the list of available options for curations is defined in [PackageCurationData.kt](https://github.com/oss-review-toolkit/ort/blob/main/model/src/main/kotlin/PackageCurationData.kt).