Fix canonicalization scoring when library shares package name (#3551)

The code and the comment for the code are opposite.
diff --git a/lib/src/model/canonicalization.dart b/lib/src/model/canonicalization.dart
index 9dd234f..d664554 100644
--- a/lib/src/model/canonicalization.dart
+++ b/lib/src/model/canonicalization.dart
@@ -58,7 +58,7 @@
     }
 
     // Give a big boost if the library has the package name embedded in it.
-    if (library.package.namePieces.intersection(library.namePieces).isEmpty) {
+    if (library.package.namePieces.intersection(library.namePieces).isNotEmpty) {
       scoredCandidate._alterScore(1.0, _Reason.packageName);
     }