iosxr tests: Initial work for 2.3 (#20883)

Ensure a loopback device exists for testing
Remove provider:
Default is to run task on Network, device, use delegate_to: localhost for local tasks.

test/integration/targets/iosxr_template/tests/cli/basic.yaml

@@ -6,12 +6,10 @@
     commands:
       - no interface Loopback999
     match: none
-    provider: "{{ cli }}"
 
 - name: configure device with config
   iosxr_template:
     src: basic/config.j2
-    provider: "{{ cli }}"
   register: result
 
 - assert:
@@ -22,7 +20,6 @@
 - name: check device with config
   iosxr_template:
     src: basic/config.j2
-    provider: "{{ cli }}"
   register: result
 
 - assert:
@@ -35,6 +32,5 @@
     commands:
       - no interface Loopback999
     match: none
-    provider: "{{ cli }}"
 
 - debug: msg="END cli/basic.yaml"