Update to latest version of django-maintenance-mode

This update fixes a bug where the permissions of the maintenance
mode state file are not properly maintained (due to the implementation
in python-fsutil). v0.21.1 of django maintenance mode requires the
version of python-fsutil where this bug is fixed. See
fabiocaccamo/django-maintenance-mode#172 for info.

requirements/requirements.in

@@ -15,7 +15,8 @@ django>=4.2,<5.0  # https://www.djangoproject.com/
 # Pin to <= 0.10.0 because 0.11+ introduces a bug with reading environment variables with # characters.
 django-environ<=0.10.0  # https://github.com/joke2k/django-environ
 # Turn on and off maintenance mode.
-django-maintenance-mode # https://github.com/fabiocaccamo/django-maintenance-mode
+# 0.21.1 fixes a bug with permissions of the maintenance mode file.
+django-maintenance-mode>=0.21.1 # https://github.com/fabiocaccamo/django-maintenance-mode
 # Model utilities
 django-model-utils  # https://github.com/jazzband/django-model-utils
 # login/auth using Drupal or other SocialApplications.

requirements/requirements.txt

@@ -78,7 +78,7 @@ django-filter==23.3
     # via django-anvil-consortium-manager
 django-login-required-middleware==0.9.0
     # via -r requirements/requirements.in
-django-maintenance-mode==0.21.0
+django-maintenance-mode==0.21.1
     # via -r requirements/requirements.in
 django-model-utils==4.3.1
     # via -r requirements/requirements.in
@@ -156,7 +156,7 @@ python-dateutil==2.8.2
     # via
     #   pandas
     #   pronto
-python-fsutil==0.12.0
+python-fsutil==0.13.1
     # via django-maintenance-mode
 python3-openid==3.2.0
     # via django-allauth