packaging: add configparser to inno requirements file

This dependency is missing and pip complains about it in
strict hashing mode. How this was missed, I have no clue.

Differential Revision: https://phab.mercurial-scm.org/D7973

contrib/packaging/inno/requirements.txt

@@ -8,6 +8,10 b' certifi==2019.9.11 \\'
     --hash=sha256:e4f3620cfea4f83eedc95b24abd9cd56f3c4b146dd0177e83a21b4eb49e21e50 \
     --hash=sha256:fd7c7c74727ddcf00e9acd26bba8da604ffec95bf1c2144e67aff7a8b50e6cef \
     # via dulwich
+configparser==4.0.2 \
+    --hash=sha256:254c1d9c79f60c45dfde850850883d5aaa7f19a23f13561243a050d5a7c3fe4c \
+    --hash=sha256:c7d282687a5308319bf3d2e7706e575c635b0a470342641c93bea0ea3b5331df \
+    # via entrypoints
 docutils==0.15.2 \
     --hash=sha256:6c4f696463b79f1fb8ba0c594b63840ebd41f059e92b31957c46b74a4599b6d0 \
     --hash=sha256:9e4d7ecfc600058e07ba661411a2b7de2fd0fafa17d1a7f7361cd47b1175c827 \
@@ -34,8 +38,7 b' pygments==2.4.2 \\'
     --hash=sha256:881c4c157e45f30af185c1ffe8d549d48ac9127433f2c380c24b84572ad66297
 pywin32-ctypes==0.2.0 \
     --hash=sha256:24ffc3b341d457d48e8922352130cf2644024a4ff09762a2261fd34c36ee5942 \
-    --hash=sha256:9dc2d991b3479cc2df15930958b674a48a227d5361d413827a4cfd0b5876fc98 \
-    # via keyring
+    --hash=sha256:9dc2d991b3479cc2df15930958b674a48a227d5361d413827a4cfd0b5876fc98
 urllib3==1.25.6 \
     --hash=sha256:3de946ffbed6e6746608990594d08faac602528ac7015ac28d33cee6a45b7398 \
     --hash=sha256:9a107b99a5393caf59c7aa3c1249c16e6879447533d0887f4336dde834c7be86 \