test: Make sure to test the docs

I can't believe I forgot to enable this earlier.

test.sh

@@ -65,6 +65,7 @@ if label-block "basic"; then
 	run-testsuite ./test/test-headerfmt.sh
 	run-testsuite ./test/test-markdownlint.sh
 	run-testsuite ./test/test-commit-message.sh
+	run-testsuite ./test/test-docs-generate.sh
 	run-testsuite ./test/test-govet.sh
 	run-testsuite ./test/test-examples.sh
 	run-testsuite ./test/test-gotest.sh