Update TLS expiration warning

[frednntelia]

fixing the language of the TLS certificate expiration warning

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Description

corrects the language of the warning message sent when a TLS certificate is about to expire

Fixes #(issue)

Type of change

• Other

Checklist

• [ yes] My code follows the style guidelines of this project
• I ran ESLint and other linters for modified files
• I have performed a self-review of my own code and tested it
• I have commented my code, particularly in hard-to-understand areas (including JSDoc for methods)
• My changes generates no new warnings
• My code needed automated testing. I have added them (this is optional task)

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