Merge Test to Stable (#737) (#746)

[FIX] Bug where files could not be added to drafts #742
[FIX] Remove test comparing datetime objects #744
[FIX] Draft validation issues #740
[ADD] Support for DOI as preferred identifier #741
[ADD] Support for bulk-delete api operations #725
[ADD] Enable V2 endpoints

requirements.txt

@@ -18,7 +18,7 @@ django-debug-toolbar==3.5.0; python_version >= "3.7"
 django-environ==0.4.5
 django-split-settings==1.1.0; python_version >= "3.6" and python_version < "4.0"
 django-watchman==1.3.0
-django==3.2.14; python_version >= "3.6"
+django==3.2.15; python_version >= "3.6"
 djangorestframework==3.13.1; python_version >= "3.6"
 docutils==0.16; python_version >= "3.6" and python_full_version < "3.0.0" or python_full_version >= "3.5.0" and python_version >= "3.6"
 elasticsearch==7.17.4; (python_version >= "2.7" and python_full_version < "3.0.0") or (python_full_version >= "3.4.0" and python_version < "4")