move local autograding to Make target

Author: afeld

Makefile

@@ -30,3 +30,14 @@ update_packages:
 	./extras/scripts/update_lectures.sh
 
 	echo "Please update homework notebooks separately, in python-public-policy-assignments"
+
+# based on https://gradescope-autograders.readthedocs.io/en/latest/manual_docker/
+autograde:
+	mkdir -p ./extras/autograder/results
+
+	docker run --rm \
+		-v ./extras/autograder:/autograder \
+		gradescope/autograder-base \
+		/bin/bash -c "/autograder/source/setup.sh && /autograder/source/run_autograder"
+
+	cat ./extras/autograder/results/results.json

meta/instructor_guide.md

@@ -127,18 +127,10 @@ Most of the issues are around Plotly rendering. Things that have been hit repeat
 
 ## Autograder
 
-Based on the [Gradescope instructions](https://gradescope-autograders.readthedocs.io/en/latest/manual_docker/):
+Requires [Docker](https://www.docker.com/).
 
 ```sh
-cd extras/autograder
-mkdir -p results
-
-docker run --rm \
-  -v .:/autograder \
-  gradescope/autograder-base \
-  /bin/bash -c "/autograder/source/setup.sh && /autograder/source/run_autograder"
-
-cat results/results.json
+make autograde
 ```
 {%- endif %}