refactor(PackageCurationData)!: Drop support for legacy property name

The property has been renamed more than a year ago [1] and it's easy
to make the needed alignments, see [2]. So, drop this last remaining
`@JsonAlias` annotation to eliminate technical debt.

[1]: b9e8b63
[2]: oss-review-toolkit/ort-config#96

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

model/src/main/kotlin/PackageCurationData.kt

@@ -19,7 +19,6 @@
 
 package org.ossreviewtoolkit.model
 
-import com.fasterxml.jackson.annotation.JsonAlias
 import com.fasterxml.jackson.annotation.JsonInclude
 
 import org.ossreviewtoolkit.utils.common.zip
@@ -88,7 +87,6 @@ data class PackageCurationData(
     /**
      * Whether the package is metadata only.
      */
-    @JsonAlias("is_meta_data_only")
     val isMetadataOnly: Boolean? = null,
 
     /**