[conductor] Fix branch version to use framework branch (#103381)

dev/conductor/core/lib/src/next.dart

@@ -194,10 +194,10 @@ class NextContext extends Context {
           previousCheckoutLocation: state.framework.checkoutPath,
         );
         stdio.printStatus('Writing candidate branch...');
-        bool needsCommit = await framework.updateCandidateBranchVersion(state.releaseVersion);
+        bool needsCommit = await framework.updateCandidateBranchVersion(state.framework.candidateBranch);
         if (needsCommit) {
           final String revision = await framework.commit(
-              'Create candidate branch version ${state.engine.candidateBranch} for ${state.releaseChannel}',
+              'Create candidate branch version ${state.framework.candidateBranch} for ${state.releaseChannel}',
               addFirst: true,
           );
           // append to list of cherrypicks so we know a PR is required

dev/conductor/core/test/next_test.dart

@@ -561,6 +561,7 @@ void main() {
         ]);
 
         expect(processManager, hasNoRemainingExpectations);
+        expect(stdio.stdout, contains('release-candidate-branch.version containing $candidateBranch'));
         expect(stdio.stdout, contains('Updating engine revision from $oldEngineVersion to $revision1'));
         expect(stdio.stdout, contains('Are you ready to push your framework branch'));
       });