feat(freemarker): Add val PackageModel.labels for convenient access

Package labels can be used for injecting custom data into any plain text
report. So, make it more convenient for the '.ftl' to access the labels.

Signed-off-by: Frank Viernau <[email protected]>

Author: fviernau

plugins/reporters/freemarker/src/main/kotlin/FreemarkerTemplateProcessor.kt

@@ -160,6 +160,12 @@ class FreemarkerTemplateProcessor(
          */
         val excluded: Boolean by lazy { input.ortResult.isExcluded(id) }
 
+        /**
+         * The labels for the package.
+         */
+        @Suppress("UNUSED") // This function is used in the templates.
+        val labels: Map<String, String> by lazy { input.ortResult.getPackage(id)?.metadata?.labels.orEmpty() }
+
         /**
          * The resolved license information for the package.
          */