py3: add b'' prefixes to make values bytes

# skip-blame beacuse just b'' prefixes

Differential Revision: https://phab.mercurial-scm.org/D3329

tests/test-clone-cgi.t

@@ -17,7 +17,7 b' initialize repository'
   > from mercurial import demandimport; demandimport.enable()
   > from mercurial.hgweb import hgweb
   > from mercurial.hgweb import wsgicgi
-  > application = hgweb("test", "Empty test repository")
+  > application = hgweb(b"test", b"Empty test repository")
   > wsgicgi.launch(application)
   > HGWEB
   $ chmod 755 hgweb.cgi

tests/test-clone.t

@@ -559,8 +559,8 b' iterable in addbranchrevs()'
   $ cat <<EOF > simpleclone.py
   > from mercurial import ui, hg
   > myui = ui.ui.load()
-  > repo = hg.repository(myui, 'a')
-  > hg.clone(myui, {}, repo, dest="ua")
+  > repo = hg.repository(myui, b'a')
+  > hg.clone(myui, {}, repo, dest=b"ua")
   > EOF
 
   $ $PYTHON simpleclone.py
@@ -573,8 +573,8 b' iterable in addbranchrevs()'
   > from mercurial import ui, hg, extensions
   > myui = ui.ui.load()
   > extensions.loadall(myui)
-  > repo = hg.repository(myui, 'a')
-  > hg.clone(myui, {}, repo, dest="ua", branch=["stable",])
+  > repo = hg.repository(myui, b'a')
+  > hg.clone(myui, {}, repo, dest=b"ua", branch=[b"stable",])
   > EOF
 
   $ $PYTHON branchclone.py