fix(#125): handle utcnow for transaction module

[indiVar0508]

python 3.12 has deprecated the use of datetime.datetime.utcnow infavour of datetime.datetime.now(datetime.UTC). ref: https://docs.python.org/3/library/datetime.html#datetime.datetime.utcnow

so added a utility method that tries to address this for different python version and used it in Transaction class and tests where we were setting default datetime value for datetime column.

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• Overall coverage decreased (-0.05%) to 93.622%

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Totals
Change from base Build 7207361402:	-0.05%
Covered Lines:	4888
Relevant Lines:	5152

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