run-tests: use more explicit criteria for detecting no-eol

Preparing for the situation where there could be unsalted lines not terminated
with \n.

tests/run-tests.py

@@ -690,8 +690,7 b' def tsttest(test, wd, options, replaceme'
             lout, lcmd = l.split(salt, 1)
 
         if lout:
-            if lcmd:
-                # output block had no trailing newline, clean up
+            if not lout.endswith('\n'):
                 lout += ' (no-eol)\n'
 
             # find the expected output at the current position