Update clean target to regenerate .pot

Makefile

@@ -28,7 +28,7 @@ install_deps:
 		python3-bson
 
 i18n:
-	$(PYTHON) setup.py build
+	$(PYTHON) setup.py build_i18n
 
 dryrun: probert i18n
 	$(MAKE) ui-view DRYRUN="--dry-run --bootloader uefi"

README.md

@@ -13,15 +13,16 @@ Our localization platform is Launchpad, translations are managed at
 https://translations.launchpad.net/ubuntu/+source/subiquity/
 
 To update translation template in launchpad:
- * execute $ make i18n
- * make an upload of subiquity into Ubuntu
- * wait for it to migrate
+ * update po/POTFILES.in with any new files that contain translations
+ * execute clean target, i.e. $ debuild -S
+ * dput subiquity into Ubuntu
 
 To export and update translations in subiquity:
+ * Wait for new subiquity to publish
  * Request fresh translation export from Launchpad at
 https://translations.launchpad.net/ubuntu/focal/+source/subiquity/+export
  * wait for export to generate
- * download, unpack, rename files into po directory, and commit changes
+ * download, unpack, rename .po files into po directory, and commit changes
 
 # Acquire subiquity from source
 

debian/rules

@@ -14,6 +14,7 @@ export PYBUILD_OPTION="-v"
 override_dh_auto_clean:
 	rm -f .subiquity/subiquity-debug.log installer/geninstaller.log
 	rm -rf probert/
+	python3 setup.py build_i18n
 	dh_auto_clean
 
 override_dh_install: