update requirements.txt

python/requirements.txt

 numpy>=1.12, <=1.16.4 ; python_version<"3.5"
-shapely==1.7.0
+shapely==1.8.0
 wheel>=0.34.0, <0.35.0
 setuptools>=44.1.0
 google>=2.0.3
@@ -16,8 +16,8 @@ pyclipper==1.2.1
 MarkupSafe==1.1.1
 Werkzeug==1.0.1
 ujson>=2.0.3
-sentencepiece==0.1.92; platform_machine !=  "aarch64"
+sentencepiece==0.1.96; platform_machine !=  "aarch64"
 sentencepiece; platform_machine ==  "aarch64"
-opencv-python==4.2.0.32; platform_machine !=  "aarch64"
+opencv-python<=4.2.0.32; platform_machine !=  "aarch64"
 opencv-python; platform_machine == "aarch64"
 pytest