Fix typos (and trailing ws) reported by codespell

docs/tutorial.rst

@@ -162,12 +162,12 @@ above are already provided for 99% of services by the HTTP mix-in module. It
 looks much simpler when we look at the actual implementations of the two
 new-style indexing listers we currently have…
 
-When developing a new lister, it's important to test. For this, add the tests 
-(check `swh/lister/*/tests/`) and register the celery tasks in the main 
+When developing a new lister, it's important to test. For this, add the tests
+(check `swh/lister/*/tests/`) and register the celery tasks in the main
 conftest.py (`swh/lister/core/tests/conftest.py`).
 
-Another important step is to actually run it within the 
-docker-dev (:ref:`run-lister-tutorial`). 
+Another important step is to actually run it within the
+docker-dev (:ref:`run-lister-tutorial`).
 
 This is the entire source code for the BitBucket repository lister::
 

swh/lister/cran/tests/conftest.py

@@ -15,7 +15,7 @@ def lister_cran(swh_listers):
     # Add the load-deb-package in the scheduler backend
     lister.scheduler.create_task_type({
         'type': 'load-archive-files',
-        'description': 'Load archive files',
+        'description': 'Load archive files.',
         'backend_name': 'swh.loader.package.tasks.LoadArchive',
         'default_interval': '1 day',
     })

swh/lister/gnu/tests/conftest.py

@@ -15,7 +15,7 @@ def lister_gnu(swh_listers):
     # Add the load-deb-package in the scheduler backend
     lister.scheduler.create_task_type({
         'type': 'load-archive-files',
-        'description': 'Load archive files',
+        'description': 'Load archive files.',
         'backend_name': 'swh.loader.package.tasks.LoadArchive',
         'default_interval': '1 day',
     })

swh/lister/gnu/tests/find_tarballs_output.json

@@ -179,4 +179,4 @@
       "archive": "https://ftp.gnu.org/old-gnu/xboard/xboard-4.2.7.tar.gz",
       "date": "1070057764"
     }
-  ]  
+  ]