tests: prove that ignore works

tests/test-pager.t

@@ -204,3 +204,21 b' explicit flags work too:'
    8: a 8
    9: a 9
   10: a 10
+
+Put annotate in the ignore list for pager:
+  $ cat >> $HGRCPATH <<EOF
+  > [pager]
+  > ignore = annotate
+  > EOF
+  $ hg blame a
+   0: a
+   1: a 1
+   2: a 2
+   3: a 3
+   4: a 4
+   5: a 5
+   6: a 6
+   7: a 7
+   8: a 8
+   9: a 9
+  10: a 10