feat: add Cloud Client library samples for Chat

[PierrickVoulet]

Has it been tested?

• Development testing done

Checklist

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have performed a peer-reviewed with team member(s)
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• Any dependent changes have been merged and published in downstream modules

[snippet-bot]

Here is the summary of changes.

You are about to add 27 region tags.

• chat/client-libraries/cloud/authentication_utils.py:19, tag chat_authentication_utils
• chat/client-libraries/cloud/create_membership_user_cred.py:22, tag chat_create_membership_user_cred
• chat/client-libraries/cloud/create_membership_user_cred_for_app.py:21, tag chat_create_membership_user_cred_for_app
• chat/client-libraries/cloud/create_message_app_cred.py:21, tag chat_create_message_app_cred
• chat/client-libraries/cloud/create_message_app_cred_with_cards.py:21, tag chat_create_message_app_cred_with_cards
• chat/client-libraries/cloud/create_message_user_cred.py:21, tag chat_create_message_user_cred
• chat/client-libraries/cloud/create_message_user_cred_at_mention.py:22, tag chat_create_message_user_cred_at_mention
• chat/client-libraries/cloud/create_message_user_cred_message_id.py:22, tag chat_create_message_user_cred_message_id
• chat/client-libraries/cloud/create_message_user_cred_request_id.py:22, tag chat_create_message_user_cred_request_id
• chat/client-libraries/cloud/create_message_user_cred_thread_key.py:21, tag chat_create_message_user_cred_thread_key
• chat/client-libraries/cloud/create_message_user_cred_thread_name.py:22, tag chat_create_message_user_cred_thread_name
• chat/client-libraries/cloud/delete_message_app_cred.py:21, tag chat_delete_message_app_cred
• chat/client-libraries/cloud/delete_message_user_cred.py:21, tag chat_delete_message_user_cred
• chat/client-libraries/cloud/get_membership_app_cred.py:21, tag chat_get_membership_app_cred
• chat/client-libraries/cloud/get_membership_user_cred.py:21, tag chat_get_membership_user_cred
• chat/client-libraries/cloud/get_message_app_cred.py:21, tag chat_get_message_app_cred
• chat/client-libraries/cloud/get_message_user_cred.py:21, tag chat_get_message_user_cred
• chat/client-libraries/cloud/get_space_app_cred.py:21, tag chat_get_space_app_cred
• chat/client-libraries/cloud/get_space_user_cred.py:21, tag chat_get_space_user_cred
• chat/client-libraries/cloud/list_memberships_app_cred.py:21, tag chat_list_memberships_app_cred
• chat/client-libraries/cloud/list_memberships_user_cred.py:21, tag chat_list_memberships_user_cred
• chat/client-libraries/cloud/list_messages_user_cred.py:21, tag chat_list_messages_user_cred
• chat/client-libraries/cloud/list_spaces_app_cred.py:21, tag chat_list_spaces_app_cred
• chat/client-libraries/cloud/list_spaces_user_cred.py:21, tag chat_list_spaces_user_cred
• chat/client-libraries/cloud/update_message_app_cred.py:21, tag chat_update_message_app_cred
• chat/client-libraries/cloud/update_message_user_cred.py:22, tag chat_update_message_user_cred
• chat/client-libraries/cloud/update_space_user_cred.py:22, tag chat_update_space_user_cred

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