phabricator: make it clear what happen when no response

Differential Revision: https://phab.mercurial-scm.org/D8621

hgext/phabricator.py

@@ -1650,7 +1650,7 b' def _confirmbeforesend(repo, revs, oldma'
         )
 
     if ui.promptchoice(
-        _(b'Send the above changes to %s (yn)?$$ &Yes $$ &No') % url
+        _(b'Send the above changes to %s (Y/n)?$$ &Yes $$ &No') % url
     ):
         return False
 

tests/test-phabricator.t

@@ -670,7 +670,7 b' The folding of immutable commits works..'
   NEW - a959a3f69d8d: one: first commit to review
   NEW - 24a4438154ba: two: second commit to review
   NEW - d235829e802c: 3: a commit with no detailed message
-  Send the above changes to https://phab.mercurial-scm.org/ (yn)? y
+  Send the above changes to https://phab.mercurial-scm.org/ (Y/n)? y
   D8387 - created - a959a3f69d8d: one: first commit to review
   D8387 - created - 24a4438154ba: two: second commit to review
   D8387 - created - d235829e802c: 3: a commit with no detailed message
@@ -734,7 +734,7 b' updated.'
   D8387 - 602c4e738243: one: first commit to review
   D8387 - 0124e5474c88: two: second commit to review
   D8387 - e4edb1fe3565: 3: a commit with no detailed message
-  Send the above changes to https://phab.mercurial-scm.org/ (yn)? y
+  Send the above changes to https://phab.mercurial-scm.org/ (Y/n)? y
   D8387 - updated - 602c4e738243: one: first commit to review
   D8387 - updated - 0124e5474c88: two: second commit to review
   D8387 - updated - e4edb1fe3565: 3: a commit with no detailed message