fix env var in actions (mne-tools#13844)

Co-authored-by: Scott Huberty <52462026+scott-huberty@users.noreply.github.com>

Author: drammock

tools/github_actions_download.sh

@@ -1,6 +1,6 @@
 #!/bin/bash -ef
 
-if [ "${DEPS}" != "minimal" ]; then
+if [ "${MNE_CI_KIND}" != "minimal" ]; then
 	python -c 'import mne; mne.datasets.testing.data_path(verbose=True)';
 	python -c "import mne; mne.datasets.misc.data_path(verbose=True)";
 fi