Use Middleman external pipeline for Tailwind

Remove CI step that ran tailwindcss during deploy and rely on the
external_pipeline configured in config.rb
Commit the generated source/stylesheets/site.css and remove it
from .gitignore

Author: thibaudgg

.github/workflows/deploy.yml

@@ -27,10 +27,7 @@ jobs:
         with:
           bundler-cache: true
 
-      - name: Generate Tailwind CSS
-        run: bundle exec tailwindcss -i source/stylesheets/tailwind.css -o source/stylesheets/site.css --minify
-
-      - name: Build site with Middleman
+      - name: Build site
         run: bundle exec middleman build
 
       - name: Setup Pages

.gitignore

@@ -3,4 +3,3 @@
 .DS_Store
 build/
 .tmp/
-source/stylesheets/site.css

config.rb

@@ -4,19 +4,19 @@
 # https://middlemanapp.com/advanced/configuration/#environment-specific-settings
 set :url_root, @app.data.site.host
 
+activate :external_pipeline,
+         name: :tailwindcss,
+         command: build? ? 'tailwindcss -i source/stylesheets/tailwind.css -o source/stylesheets/site.css --minify' : 'tailwindcss -i source/stylesheets/tailwind.css -o source/stylesheets/site.css --watch --minify',
+         source: 'source',
+         latency: 1
+
 activate :livereload
 activate :i18n,
          mount_at_root: :en,
          lang_map: { fr: :acp, de: :solawi }
 
 configure :development do
   set :debug_assets, true
-
-  activate :external_pipeline,
-           name: :tailwindcss,
-           command: 'tailwindcss -i source/stylesheets/tailwind.css -o source/stylesheets/site.css --watch',
-           source: 'source',
-           latency: 1
 end
 
 configure :build do