tests: add `revlogutils.deltas` module to doctests
The doctest in these module have been from `mercurial.revlog` but the module was
not added to the doctests.
Spotted by Yuya Nishihara.
--- a/tests/test-doctest.py Thu Nov 15 20:20:31 2018 +0900
+++ b/tests/test-doctest.py Tue Nov 13 14:41:04 2018 +0100
@@ -61,6 +61,7 @@
testmod('mercurial.parser')
testmod('mercurial.pycompat')
testmod('mercurial.revlog')
+testmod('mercurial.revlogutils.deltas')
testmod('mercurial.revsetlang')
testmod('mercurial.smartset')
testmod('mercurial.store')