[dart fix]Fix adding package to both dependencies and dev_dependencies in pubspec.

Closes https://github.com/dart-lang/sdk/issues/63409

Change-Id: I51258cf986b9b60a8d7add58f7737d6c8bf9f1ac
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/505040
Commit-Queue: Keerti Parthasarathy <keertip@google.com>
Reviewed-by: Brian Wilkerson <brianwilkerson@google.com>

pkg/analysis_server/lib/src/services/correction/bulk_fix_processor.dart

@@ -423,7 +423,7 @@ class BulkFixProcessor {
         var result = await _runPubspecValidatorAndFixGenerator(
           FileSource(pubspecFile),
           pubspecDeps.packages,
-          pubspecDeps.devPackages,
+          pubspecDeps.devPackages.difference(pubspecDeps.packages),
           context.contextRoot.resourceProvider,
         );
         if (result.isNotEmpty) {

pkg/analysis_server/test/src/services/correction/fix/bulk_fix_processor_test.dart

@@ -270,6 +270,29 @@ void bad() {
 
 @reflectiveTest
 class PubspecFixTest extends BulkFixProcessorTest {
+  Future<void> test_dedupe_devPackages_against_packages() async {
+    var content = '''
+name: test
+''';
+    var expected = '''
+name: test
+dependencies:
+  b: any
+''';
+    updateTestPubspecFile(content);
+
+    newFile('$testPackageLibPath/lib.dart', '''
+import 'package:b/b.dart';
+''');
+
+    var testFile = newFile('$testPackageTestPath/test.dart', '''
+import 'package:b/b.dart';
+''');
+
+    await getResolvedUnit(testFile);
+    await assertFixPubspec(content, expected);
+  }
+
   Future<void> test_delete_change() async {
     var content = '''
 name: test