test: Remove some races from check-reauthorize

Just wait for the full expected texts instead of waiting for some text
and then asserting that is has the right content.  With the old way,
we could easily pick up previous results.

Closes #8510

test/verify/check-reauthorize

@@ -64,9 +64,7 @@ class TestReauthorize(MachineCase):
         self.login_and_go("/playground/test")
 
         b.click(".super-channel .btn")
-        b.wait_in_text(".super-channel span", 'result: ')
-
-        self.assertIn('result: uid=0', b.text(".super-channel span"))
+        b.wait_in_text(".super-channel span", 'result: uid=0')
 
         # Deauthorize
         b.leave_page()
@@ -79,16 +77,13 @@ class TestReauthorize(MachineCase):
         b.enter_page("/playground/test")
 
         b.click(".super-channel .btn")
-        b.wait_in_text(".super-channel span", 'result:')
-
-        self.assertEqual(b.text(".super-channel span"), 'result: access-denied')
+        b.wait_in_text(".super-channel span", 'result: access-denied')
 
         # Now log in as root even without password caching
         b.logout()
         self.login_and_go("/playground/test", authorized=False, user="root")
         b.click(".super-channel .btn")
-        b.wait_in_text(".super-channel span", 'result: ')
-        self.assertIn('result: uid=0', b.text(".super-channel span"))
+        b.wait_in_text(".super-channel span", 'result: uid=0')
 
         # When root and not authorized, the 'Locked' or 'Unlocked' indicators should not be visible
         b.leave_page()