Remove more remnants of askbot

.gitmodules

-[submodule "askbot"]
-	path = askbot
-	url = git@github.com:MITx/askbot-devel.git

askbot @ e56ae380

-Subproject commit e56ae380846f7c6cdaeacfc58880fab103540491

lms/envs/test.py

@@ -77,7 +77,6 @@ XQUEUE_WAITTIME_BETWEEN_REQUESTS = 5 # seconds
 STATICFILES_DIRS = [
     COMMON_ROOT / "static",
     PROJECT_ROOT / "static",
-    ASKBOT_ROOT / "askbot" / "skins",
 ]
 STATICFILES_DIRS += [
     (course_dir, COMMON_TEST_DATA_ROOT / course_dir)

lms/static/sass/course.scss

@@ -47,16 +47,3 @@
 // instructor
 @import "course/instructor/instructor";
 
-// Askbot / Discussion styles
-@import "course/discussion/askbot-original";
-@import "course/discussion/discussion";
-@import "course/discussion/sidebar";
-@import "course/discussion/questions";
-@import "course/discussion/tags";
-@import "course/discussion/question-view" ;
-@import "course/discussion/answers";
-@import "course/discussion/forms";
-@import "course/discussion/form-wmd-toolbar";
-@import "course/discussion/modals";
-@import "course/discussion/profile";
-@import "course/discussion/badges";