Fix timestamptz read carto

[Mmoncadaisla]

Context

In this small PR from Support we aim to fix a small bug in the pg2dtypes function which causes timestamp with time zone dtypes columns to be read as object data type columns in GeoPandas.

Further details can be found in this CH story.

PR changes

• utils: fix the small typo causing the error for timestamptz dtype
• test_utils: fix corresponding unit test

Result with PR changes

>>> import cartoframes
>>> cartoframes.auth.set_default_credentials(username='mmoncada', api_key='1d9f28a0e83f7793c371ecc4cd4be5e87ac0687c')
>>> gdf = cartoframes.read_carto('test_timestamptz_cartoframes')
>>> gdf.dtypes
cartodb_id                  int64
the_geom                 geometry
field_1                     int64
county_fip                  int64
fips                        int64
housing_un                 object
county                     object
state_name                 object
created_at    datetime64[ns, UTC]
updated_at    datetime64[ns, UTC]
state_fips                  int64
monday                      int64
tuesday                     int64
wednesday                   int64
thursday                    int64
dtype: object

[Jesus89]

Good catch!