Use shell module to generate keys

openssh_keypair ansible module was moved to community.crypto
collection from Ansible-Core 2.11, we can't use it now.
For using it in the product we either need to package and add to
deps and maintain the whole community.crypto module, either to
use 'shell' command to generate the keys.
Added "creates" so keys won't be overridden if they exists,
keeping the idempotency. [1]

[1] https://github.com/ansible-collections/community.crypto/blob/
91d98c44137cde53726bfa8f61898f3c28041e20/plugins/module_utils/openssh/backends/common.py#L188

Change-Id: Ib9a31518ee9408d89abff4c4eb18a7cfe243fb58

tripleo_ansible/roles/octavia_undercloud/tasks/main.yml

@@ -58,8 +58,9 @@
         state: directory
 
     - name: Generate ssh key for Octavia
-      openssh_keypair:
-        path: "{{ ssh_key_dir }}/octavia_id_rsa"
+      shell: "ssh-keygen -q -t rsa -N '' -f {{ ssh_key_dir }}/octavia_id_rsa"
+      args:
+        creates: "{{ ssh_key_dir }}/octavia_id_rsa"
       no_log: "{{ octavia_undercloud_config_hide_sensitive_logs | bool }}"
 
     - name: Set ssh key path fact

tripleo_ansible/roles/tripleo_transfer/tasks/main.yml

@@ -36,20 +36,28 @@
         - "{{ tripleo_transfer_dest_host }}"
 
     - name: generate ssh key-pair in source host
-      community.crypto.openssh_keypair:
-        path: "{{ tripleo_transfer_key_location }}"
+      shell: "ssh-keygen -t rsa -q -N '' -f {{ tripleo_transfer_key_location }}"
+      args:
+        creates: "{{ tripleo_transfer_key_location }}"
+      delegate_to: "{{ tripleo_transfer_src_host }}"
+      become: "{{ tripleo_transfer_src_become }}"
+      register: keypair_generation
+
+    - name: register public key
+      command: "cat {{ tripleo_transfer_key_location }}.pub"
       delegate_to: "{{ tripleo_transfer_src_host }}"
       become: "{{ tripleo_transfer_src_become }}"
       register: keypair_gen
+      when: keypair_generation is succeeded
 
     - name: set authorized-keys in destination host
       authorized_key:
         comment: "Added by tripleo-transfer"
         user: "{{ ansible_user|default(ansible_ssh_user|default(hostvars[tripleo_transfer_dest_host].ansible_user_id)) }}"
         state: present
-        key: "{{ keypair_gen.public_key }}"
+        key: "{{ keypair_gen.stdout }}"
       delegate_to: "{{ tripleo_transfer_dest_host }}"
-      when: keypair_gen is succeeded
+      when: keypair_generation is succeeded
 
     - import_tasks: flag.yml
       when: