feat(git-node): add backport reviewers to metadata

Author: aduh95

lib/metadata_gen.js

@@ -48,13 +48,11 @@ export default class MetadataGenerator {
       meta.unshift(`Backport-PR-URL: ${prUrl}`);
       meta.unshift(`PR-URL: ${altPrUrl}`);
     } else {
-      // Reviews are only added here as backports should not contain reviews
-      // for the backport itself in the metadata
       meta.unshift(`PR-URL: ${prUrl}`);
-      meta.push(
-        ...reviewedBy.map((r) => `Reviewed-By: ${r.reviewer.getContact()}`)
-      );
     }
+    meta.push(
+      ...reviewedBy.map((r) => `Reviewed-By: ${r.reviewer.getContact()}`)
+    );
     meta.push(''); // creates final EOL
     return meta.join('\n');
   }

test/unit/metadata_gen.test.js

@@ -45,6 +45,10 @@ const backportExpected = `PR-URL: https://github.com/nodejs/node/pull/29995
 Backport-PR-URL: https://github.com/nodejs/node/pull/30072
 Fixes: https://github.com/nodejs/build/issues/1961
 Refs: https://github.com/nodejs/node/commit/53ca0b9ae145c430842bf78e553e3b6cbd2823aa#commitcomment-35494896
+Reviewed-By: Foo User <foo@example.com>
+Reviewed-By: Quux User <quux@example.com>
+Reviewed-By: Baz User <baz@example.com>
+Reviewed-By: Bar User <bar@example.com>
 `;
 
 const selfRefData = Object.assign({}, data, { pr: selfRefPR });