PerformanceWarning instances raised on population dataframe creation

[matt-graham]

Since the update to pandas v2 we get a series of warnings

PerformanceWarning: DataFrame is highly fragmented.  This is usually the result of calling `frame.insert` many times, which has poor performance.  Consider joining all columns at once using pd.concat(axis=1) instead. To get a de-fragmented frame, use `newframe = frame.copy()`

from the lines

TLOmodel/src/tlo/population.py

Lines 64 to 67 in dcdf014

	props = pd.DataFrame(index=pd.RangeIndex(stop=size, name="person"))
	for module in self.sim.modules.values():
	for prop_name, prop in module.PROPERTIES.items():
	props[prop_name] = prop.create_series(prop_name, size)

I'm not sure, but I think the performance issue mentioned is with respect to the cost of creating a dataframe with lots of columns by inserting one by one rather than adding altogether, rather than having an implication for the subsequent cost of accessing data in that dataframe (which would be much more of an issue in our case), but it would still be worth fixing this to avoid the warnings.

Originally posted by @matt-graham in #1159 (comment)