Install Bikeshed from PyPI instead of Git clone

.travis.yml

@@ -14,16 +14,12 @@ cache: pip
 before_install:
 - chmod 755 ./.deploy-output.sh
 install:
-- pip install --upgrade setuptools        
-- pip install pygments cssselect html5lib lxml
-- git clone --depth=100 --branch=main https://github.com/tabatkins/bikeshed.git ./bikeshed
-- pip install --editable ./bikeshed
+- pip install bikeshed
 - |
   if "${USE_BIKESHED_CACHE}"; then
     # Use cached copy of bikeshed data files to give consistent builds
-    #- bikeshed update
-    cp -R .spec-data/* ./bikeshed/bikeshed/spec-data
-    cp -R .bikeshed-include/* ./bikeshed/bikeshed/boilerplate/webauthn
+    rsync -aP --delete .spec-data/ "${VIRTUAL_ENV}"/lib/python3.7/site-packages/bikeshed/spec-data/
+    rsync -aP --delete .bikeshed-include/ "${VIRTUAL_ENV}"/lib/python3.7/site-packages/bikeshed/boilerplate/webauthn/
   fi
 script: 'bikeshed spec'
 after_success: