202012 branch is using reproducible build. The versions-py3 file must contains correct pip3 package version. Otherwise we will get a build error
```
Step 31/74 : RUN pip3 install scapy==2.4.4 pyroute2==0.5.14 netifaces==0.10.9
---> Running in d7a2401dd21d
Collecting scapy==2.4.4
Downloading scapy-2.4.4.tar.gz (1.0 MB)
Collecting pyroute2==0.5.14
Downloading pyroute2-0.5.14.tar.gz (873 kB)
ERROR: Cannot install netifaces==0.10.9 because these package versions have conflicting dependencies.
The conflict is caused by:
The user requested netifaces==0.10.9
The user requested (constraint) netifaces==0.10.7
To fix this you could try to:
1. loosen the range of package versions you've specified
2. remove package versions to allow pip attempt to solve the dependency conflict
ERROR: ResolutionImpossible: for help visit https://pip.pypa.io/en/latest/user_guide/#fixing-conflicting-dependencies
The command '/bin/sh -c pip3 install scapy==2.4.4 pyroute2==0.5.14 netifaces==0.10.9' returned a non-zero code: 1
[ FAIL LOG END ] [ target/docker-sonic-vs.gz ]
```
