Avoiding pFlow charge comparisons to zero and using isCharged() instead
@mhodgkin reported in ATLJETMET-796 that the charge of the pFlow object is compared to != 0.0 instead of using FLT_MIN. This has been hopefully changed now in all instances and also the comparisons to 1e-9 where changed to FLT_MIN
A similar MR was created for release 21.0, see 27736. A separate MR was used instead of picking targeting also 21.2 due to some file differences between 21.0 and 21.2
Also tagging @wbalunas, @williams and @khoo for their information.