Bump version to 4

Remove galleria keyword.

pyproject.toml

@@ -4,7 +4,7 @@ build-backend = 'flit_core.buildapi'
 
 [project]
 name = '153957-theme'
-version = '3.0'
+version = '4.0'
 description = 'Theme for sigal generated photo albums'
 readme = 'README.md'
 requires-python = '>=3.11'
@@ -19,7 +19,6 @@ keywords = [
     'photo album',
     'theme',
     'sigal',
-    'galleria',
 ]
 classifiers = [
     'Environment :: Plugins',