Replace all calls to os.Remove/os.RemoveAll by retrying util.Remove/util.RemoveAll and remove circular dependencies from util.

Fix #12339

Signed-off-by: Andrew Thornton <art27@cantab.net>
Co-authored-by: silverwind <me@silverwind.io>

* Fix data race in testlogger

* Update git_helper_for_declarative_test.go

Signed-off-by: Tamal Saha <tamal@appscode.com>

* Prevent creating empty sessions

Signed-off-by: Andrew Thornton <art27@cantab.net>

* Update modules/setting/session.go

* Remove unnecessary option

Signed-off-by: Andrew Thornton <art27@cantab.net>

* Add destory to list of ignored misspellings

* rename cookie.go -> virtual.go

* Delete old file

* Add test to ensure that sessions are not created without being logged in

Signed-off-by: Andrew Thornton <art27@cantab.net>

* fix tests

Signed-off-by: Andrew Thornton <art27@cantab.net>

* Update integrations/create_no_session_test.go