packaging: merge the requirements.txt files for WiX and Inno

Now that the content is common, there's no need to have separate files.  The
content still differs from the non-Windows platforms though.

Differential Revision: https://phab.mercurial-scm.org/D8066

contrib/packaging/hgpackaging/inno.py

@@ -66,7 +66,7 b' def build('
     staging_dir = inno_build_dir / 'stage'
 
     requirements_txt = (
-        source_dir / 'contrib' / 'packaging' / 'inno' / 'requirements.txt'
+        source_dir / 'contrib' / 'packaging' / 'requirements_win32.txt'
     )
 
     inno_build_dir.mkdir(parents=True, exist_ok=True)

contrib/packaging/hgpackaging/wix.py

@@ -343,7 +343,7 b' def build_installer('
     dist_dir = source_dir / 'dist'
     wix_dir = source_dir / 'contrib' / 'packaging' / 'wix'
 
-    requirements_txt = wix_dir / 'requirements.txt'
+    requirements_txt = 'requirements_win32.txt'
 
     build_py2exe(
         source_dir,

contrib/packaging/requirements_win32.txt

@@ -2,7 +2,7 b''
 # This file is autogenerated by pip-compile
 # To update, run:
 #
-#    pip-compile --generate-hashes --output-file=contrib/packaging/wix/requirements.txt contrib/packaging/wix/requirements.txt.in
+#    pip-compile --generate-hashes --output-file=contrib/packaging/requirements_win32.txt contrib/packaging/requirements_win32.txt.in
 #
 certifi==2019.9.11 \
     --hash=sha256:e4f3620cfea4f83eedc95b24abd9cd56f3c4b146dd0177e83a21b4eb49e21e50 \