allow_overwrite_of_existing_spreadsheet_cells to true or false

[djhmateer]

on ghsheet_feeder_db

[msramalho]

will review next week

[msramalho]

This change feels way too verbose, I don't feel it's useful to have new logs that simply say "this cell is empty" for every cell in a row of cells, so multiple entries per archive. Proposal keeps new logic with current level of verbosity.

Suggested change

	if val and gw.col_exists(col):
	existing_value = gw.get_cell(row_values, col)
	if existing_value:
	if self.allow_overwrite_of_spreadsheet_cells:
	logger.info(f"Overwriting spreadsheet cell {col}={existing_value} with {final_value}")
	else:
	logger.warning(f"NOT overwriting spreadsheet cell {col}={existing_value} with {final_value}")
	return
	else:
	logger.info(f"No existing value for {col}")
	if val and gw.col_exists(col) and (gw.get_cell(row_values, col) == "" or self.allow_overwrite_of_spreadsheet_cell):