qa/tasks/vstart_runner.py: use StringIO for capturing text

to be consistent with 8bfe977854686149c74de3ebaed7b571d43404dd

Fixes: https://tracker.ceph.com/issues/45246
Signed-off-by: Kefu Chai <kchai@redhat.com>
(cherry picked from commit 2de78c3bd9eed9bec235b68e8e52b4635e9add61)

diff --git a/qa/tasks/vstart_runner.py b/qa/tasks/vstart_runner.py
index afaf972552e46aa4f319f2550c7ff1d4eacd5ffd..481db91216b12ce971faa35e5a62ae11f54b5063 100644 (file)
--- a/qa/tasks/vstart_runner.py
+++ b/qa/tasks/vstart_runner.py
@@ -602,7 +602,7 @@ class LocalCephManager(CephManager):
         if watch_channel is not None:
             args.append("--watch-channel")
             args.append(watch_channel)
-        proc = self.controller.run(args=args, wait=False, stdout=BytesIO())
+        proc = self.controller.run(args=args, wait=False, stdout=StringIO())
         return proc
 
     def raw_cluster_cmd(self, *args, **kwargs):