[airlift] Tweak ports to 3000 in tutorial, update readme (#23986)

## Summary

Update to use port 3000. Also add some env vars we need on the dagster
end (that we lost when we moved off makefile)


## Changelog [Docs]

`NOCHANGELOG`

examples/experimental/dagster-airlift/README.md

@@ -104,9 +104,13 @@ This function creates:
 - An external asset representing each DAG. This asset is marked as materialized whenever a DAG run completes.
 - A sensor that polls the Airflow instance for operational information. This sensor is responsible for creating materializations when a DAG executes. The sensor must remain on in order to properly update execution status.
 
-Let's run Dagster to see the asset created from our Airflow DAG:
+Let's set up some environment variables, and then point Dagster to see the asset created from our Airflow DAG:
 
 ```bash
+# Set up environment variables to point to the examples/tutorial-example directory on your machine
+export TUTORIAL_EXAMPLE_DIR=...
+export DBT_PROJECT_DIR="$TUTORIAL_EXAMPLE_DIR/tutorial_example/shared/dbt"
+export AIRFLOW_HOME="$TUTORIAL_EXAMPLE_DIR/.airflow_home"
 dagster dev -f airlift.py
 ```
 

examples/experimental/dagster-airlift/examples/tutorial-example/Makefile

@@ -9,7 +9,7 @@ export DAGSTER_HOME := $(MAKEFILE_DIR)/.dagster_home
 export AIRFLOW_HOME := $(MAKEFILE_DIR)/.airflow_home
 export DBT_PROJECT_DIR := $(MAKEFILE_DIR)/tutorial_example/shared/dbt
 export DBT_PROFILES_DIR := $(MAKEFILE_DIR)/tutorial_example/shared/dbt
-export DAGSTER_URL := http://localhost:3333
+export DAGSTER_URL := http://localhost:3000
 
 help:
 	@egrep -h '\s##\s' $(MAKEFILE_LIST) | sort | awk 'BEGIN {FS = ":.*?## "}; {printf "\033[36m%-20s\033[0m %s\n", $$1, $$2}'
@@ -37,4 +37,4 @@ airflow_run:
 	airflow standalone
 
 dagster_run:
-	dagster dev -m tutorial_example.dagster_defs.definitions -p 3333
+	dagster dev -m tutorial_example.dagster_defs.definitions -p 3000