Update dependency nexmo to v2.9.0

[mend-for-github-com]

This PR contains the following updates:

Package	Type	Update	Change
nexmo	dependencies	minor	2.8.0 -> 2.9.0

By merging this PR, the issue #6 will be automatically resolved and closed:

Severity	CVSS Score	CVE
Critical	9.8	CVE-2021-3918
High	7.5	CVE-2022-24999

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Release Notes

nexmo/nexmo-node (nexmo)

v2.9.0

Compare Source

• FIXED: #​295 - Nexmo constructor changes of given options object
• ADDED: Optional target_api_key parameter for the number.buy() and number.cancel() methods.
• ADDED: Typings for Messages API
• UPDATED: Private Key strings now replaces \n with newlines for easier usage in environment variables.

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