test-annotate: fix up expected output for pure

This is just a side effect of surfacing the "revisions were skipped"
state in the blame output.

Differential Revision: https://phab.mercurial-scm.org/D956

tests/test-annotate.t

@@ -261,8 +261,8 because the pure code comes up with slig
 
   $ hg annotate -nlf b --skip 6
   0 a:1: a
-  0 a:1: z (pure !)
-  1 a:2* z
+  1 a:2* z (no-pure !)
+  0 a:1* z (pure !)
   1 a:3: a
   3 b:4: b4
   4 b:5: c