Add API to check if sensor is in trigger mode

[iche033]

🎉 New feature

Summary

Added Sensor::IsTriggered function.

Checklist

• Signed all commits for DCO
• Added tests
• Added example and/or tutorial
• Updated documentation (as needed)
• Updated migration guide (as needed)
• Consider updating Python bindings (if the library has them)
• codecheck passed (See contributing)
• All tests passed (See test coverage)
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[shameekganguly]

Thanks!