feat(iam): add iam deny samples

[FrodoTheTrue]

[snippet-bot[bot]]

Here is the summary of changes.

You are about to add 5 region tags.

• iam/deny/createDenyPolicy.js:29, tag iam_create_deny_policy
• iam/deny/deleteDenyPolicy.js:22, tag iam_delete_deny_policy
• iam/deny/getDenyPolicy.js:22, tag iam_get_deny_policy
• iam/deny/listDenyPolicies.js:22, tag iam_list_deny_policy
• iam/deny/updateDenyPolicy.js:25, tag iam_update_deny_policy

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