Fix YAML metadata errors

README.md

@@ -7,7 +7,7 @@ tags:
   - scikit-learn
   - linear-regression
   - time-series
-pipeline_tag: regression
+pipeline_tag: tabular-regression
 metrics:
   - r2_score
   - mean_squared_error
@@ -16,10 +16,10 @@ model-index:
   - name: Passenger Prediction
     results:
       - task:
-          type: Regression
+          type: tabular-regression
           name: Passenger Prediction
         dataset:
-          type: Air Passengers Prediction System
+          type: air-passengers-prediction-system
           name: Air Passengers Prediction System
         metrics:
           - type: r2_score