Use template_card instead of text messages for the WeCom notification provider

[darkclip]

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Description

Use template_card instead of text messages for the WeCom notification provider
Just got time to revisit this one. Since my old fork is too far behind master branch, ff seems to be an easier option.

Type of change

• New feature (non-breaking change which adds functionality)

Checklist

• 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)

Screenshots (if any)

Event	before	after
UP
DOWN
Cert-expiry
Testing

[darkclip]

@CommanderStorm gentle ping ^^

[CommanderStorm]

Sorry to request another change, before we can shedule this for merging into the v2.1 merge window.

(v2.0 has closed a few days ago, bit bad timing.. sorry)

[darkclip]

no worries, just glad to contribute