Remove `run_as` from the built-in templates (#2044)

## Changes

This removes the `run-as` property from the default templates. It's a
useful property but it still only works for jobs and it makes the
default databricks.yml a bit longer. It seems like users can just learn
about it from the docs and/or vary their deployment identity.

Depends on https://github.com/databricks/cli/pull/1712.

acceptance/bundle/templates/dbt-sql/output/my_dbt_sql/databricks.yml

@@ -12,12 +12,12 @@ include:
 # The default schema, catalog, etc. for dbt are defined in dbt_profiles/profiles.yml
 targets:
   dev:
-    default: true
     # The default target uses 'mode: development' to create a development copy.
     # - Deployed resources get prefixed with '[dev my_user_name]'
     # - Any job schedules and triggers are paused by default.
     # See also https://docs.databricks.com/dev-tools/bundles/deployment-modes.html.
     mode: development
+    default: true
     workspace:
       host: [DATABRICKS_URL]
 
@@ -25,10 +25,8 @@ targets:
     mode: production
     workspace:
       host: [DATABRICKS_URL]
-      # We explicitly specify /Workspace/Users/[USERNAME] to make sure we only have a single copy.
+      # We explicitly deploy to /Workspace/Users/[USERNAME] to make sure we only have a single copy.
       root_path: /Workspace/Users/[USERNAME]/.bundle/${bundle.name}/${bundle.target}
     permissions:
       - user_name: [USERNAME]
         level: CAN_MANAGE
-    run_as:
-      user_name: [USERNAME]

acceptance/bundle/templates/default-python/output/my_default_python/databricks.yml

@@ -22,10 +22,8 @@ targets:
     mode: production
     workspace:
       host: [DATABRICKS_URL]
-      # We explicitly specify /Workspace/Users/[USERNAME] to make sure we only have a single copy.
+      # We explicitly deploy to /Workspace/Users/[USERNAME] to make sure we only have a single copy.
       root_path: /Workspace/Users/[USERNAME]/.bundle/${bundle.name}/${bundle.target}
     permissions:
       - user_name: [USERNAME]
         level: CAN_MANAGE
-    run_as:
-      user_name: [USERNAME]

acceptance/bundle/templates/default-sql/output/my_default_sql/databricks.yml

@@ -35,7 +35,7 @@ targets:
     mode: production
     workspace:
       host: [DATABRICKS_URL]
-      # We explicitly specify /Workspace/Users/[USERNAME] to make sure we only have a single copy.
+      # We explicitly deploy to /Workspace/Users/[USERNAME] to make sure we only have a single copy.
       root_path: /Workspace/Users/[USERNAME]/.bundle/${bundle.name}/${bundle.target}
     variables:
       warehouse_id: f00dcafe
@@ -44,5 +44,3 @@ targets:
     permissions:
       - user_name: [USERNAME]
         level: CAN_MANAGE
-    run_as:
-      user_name: [USERNAME]

libs/template/templates/dbt-sql/template/{{.project_name}}/databricks.yml.tmpl

@@ -12,12 +12,12 @@ include:
 # The default schema, catalog, etc. for dbt are defined in dbt_profiles/profiles.yml
 targets:
   dev:
-    default: true
     # The default target uses 'mode: development' to create a development copy.
     # - Deployed resources get prefixed with '[dev my_user_name]'
     # - Any job schedules and triggers are paused by default.
     # See also https://docs.databricks.com/dev-tools/bundles/deployment-modes.html.
     mode: development
+    default: true
     workspace:
       host: {{workspace_host}}
 
@@ -25,10 +25,8 @@ targets:
     mode: production
     workspace:
       host: {{workspace_host}}
-      # We explicitly specify /Workspace/Users/{{user_name}} to make sure we only have a single copy.
+      # We explicitly deploy to /Workspace/Users/{{user_name}} to make sure we only have a single copy.
       root_path: /Workspace/Users/{{user_name}}/.bundle/${bundle.name}/${bundle.target}
     permissions:
       - {{if is_service_principal}}service_principal{{else}}user{{end}}_name: {{user_name}}
         level: CAN_MANAGE
-    run_as:
-      {{if is_service_principal}}service_principal{{else}}user{{end}}_name: {{user_name}}

libs/template/templates/default-python/template/{{.project_name}}/databricks.yml.tmpl

@@ -22,10 +22,8 @@ targets:
     mode: production
     workspace:
       host: {{workspace_host}}
-      # We explicitly specify /Workspace/Users/{{user_name}} to make sure we only have a single copy.
+      # We explicitly deploy to /Workspace/Users/{{user_name}} to make sure we only have a single copy.
       root_path: /Workspace/Users/{{user_name}}/.bundle/${bundle.name}/${bundle.target}
     permissions:
       - {{if is_service_principal}}service_principal{{else}}user{{end}}_name: {{user_name}}
         level: CAN_MANAGE
-    run_as:
-      {{if is_service_principal}}service_principal{{else}}user{{end}}_name: {{user_name}}

libs/template/templates/default-sql/template/{{.project_name}}/databricks.yml.tmpl

@@ -42,7 +42,7 @@ targets:
     mode: production
     workspace:
       host: {{workspace_host}}
-      # We explicitly specify /Workspace/Users/{{user_name}} to make sure we only have a single copy.
+      # We explicitly deploy to /Workspace/Users/{{user_name}} to make sure we only have a single copy.
       root_path: /Workspace/Users/{{user_name}}/.bundle/${bundle.name}/${bundle.target}
     variables:
       warehouse_id: {{index ((regexp "[^/]+$").FindStringSubmatch .http_path) 0}}
@@ -51,5 +51,3 @@ targets:
     permissions:
       - {{if is_service_principal}}service_principal{{else}}user{{end}}_name: {{user_name}}
         level: CAN_MANAGE
-    run_as:
-      {{if is_service_principal}}service_principal{{else}}user{{end}}_name: {{user_name}}