Update requirements-dev.txt

Author: jonashaag

requirements-dev.txt

@@ -18,9 +18,12 @@ pycodestyle
 pyupgrade
 gitpython
 gitdb
+numpydoc < 1.2
+pandas-dev-flaker
+pydata-sphinx-theme
+pytest-cython
 sphinx
 sphinx-panels
-numpydoc < 1.2
 types-python-dateutil
 types-PyMySQL
 types-pytz
@@ -51,7 +54,6 @@ statsmodels
 ipywidgets
 nbformat
 notebook>=6.0.3
-pip
 blosc
 bottleneck>=1.3.1
 ipykernel
@@ -83,7 +85,4 @@ cftime
 pyreadstat
 tabulate>=0.8.3
 natsort
-pydata-sphinx-theme
-pandas-dev-flaker==0.2.0
-pytest-cython
 setuptools>=51.0.0