junos_linkagg implementation and junos modules refactor (#26587)

* junos_linkagg implementation and junos modules refactor

*  junos_linkagg implementation
*  junos_linkagg integration test
*  net_linkagg integration test for junos
*  decouple `load_config` and `commit` operations,
   to allow single commit (in case on confirm commit) and
   to perform batch commit (multiple `load_config` followed by single
   `commit`)
*  Other related refactor

* Fix CI issues

* Fix unit test failure

test/integration/targets/junos_config/tests/netconf/single.yaml

@@ -31,6 +31,16 @@
     that:
       - "result.changed == false"
 
+- name: confirm previous commit
+  junos_config:
+    confirm_commit: yes
+    provider: "{{ netconf }}"
+  register: result
+
+- assert:
+    that:
+      - "result.changed == true"
+
 - name: teardown
   junos_config:
     lines: