eslintrc: use spaces, not tabs
eslintrc: use spaces, not tabs

Stanford-Online/edx-analytics-dashboard,edx/edx-analytics-dashboard,edx/edx-analytics-dashboard,edx/edx-analytics-dashboard,Stanford-Online/edx-analytics-dashboard,Stanford-Online/edx-analytics-dashboard,Stanford-Online/edx-analytics-dashboard,edx/edx-analytics-dashboard