Use correct max size in strftime to avoid possible out of bounds access

[MTRNord]

Proposed changes

The max size in strftime is for the dt variable and not for startMsg. (See https://man7.org/linux/man-pages/man3/strftime.3.html ) This was likely just a typo. Cppcheck was throwing an error "Buffer is accessed out of bounds: dt" for this as the dt buffer is only 128 chars not 256.

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[kzangeli]

LGTM.
Although, sizeof(dt)would be even better :)

Thank you for the contribution!!!