Bug in download function

[aronsho]

When the minimum latitude is zero, the download function does not work well (earthquakes at lower latitudes are not filtered out correctly). Here's an example code that produces the error:

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start_time = pd.to_datetime('2020/01/01')
end_time = pd.to_datetime('2022/01/01')
min_latitude = 0
max_latitude = 40
min_magnitude = 5

url = 'http://service.scedc.caltech.edu/fdsnws/event/1/query'
client = FDSNWSEventClient(url)
df_sed = client.get_events(
start_time=start_time,
end_time=end_time,
min_magnitude=min_magnitude,
min_longitude=min_longitude,
max_longitude=max_longitude,
min_latitude=min_latitude,
max_latitude=max_latitude)

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Although the minim latitude is supposed to be zero, there are earthquakes with latitudes lower than -40 present in the data. This problem is not there anymore when minimum_latitude = -1 is chosen.