remove six usage

Summary:
X-link: facebookincubator/zstrong#1002

now that python2 is long gone, lets remove dependency on six

most of the changes are in the thrift fuzzer/randomizer used in thrift tests, replacing six with what six did in the py3 case.

Reviewed By: ahilger

Differential Revision: D63709297

fbshipit-source-id: 2ff46ead9e2035c5e43081ddec8ae1e3d1499895

.github/workflows/rust-shed_linux.yml

@@ -34,8 +34,6 @@ jobs:
       run: python3 build/fbcode_builder/getdeps.py --allow-system-packages fetch --no-tests fmt
     - name: Fetch googletest
       run: python3 build/fbcode_builder/getdeps.py --allow-system-packages fetch --no-tests googletest
-    - name: Fetch python-six
-      run: python3 build/fbcode_builder/getdeps.py --allow-system-packages fetch --no-tests python-six
     - name: Fetch zstd
       run: python3 build/fbcode_builder/getdeps.py --allow-system-packages fetch --no-tests zstd
     - name: Fetch boost
@@ -104,8 +102,6 @@ jobs:
       run: python3 build/fbcode_builder/getdeps.py --allow-system-packages build --no-tests fmt
     - name: Build googletest
       run: python3 build/fbcode_builder/getdeps.py --allow-system-packages build --no-tests googletest
-    - name: Build python-six
-      run: python3 build/fbcode_builder/getdeps.py --allow-system-packages build --no-tests python-six
     - name: Build zstd
       run: python3 build/fbcode_builder/getdeps.py --allow-system-packages build --no-tests zstd
     - name: Build boost

build/fbcode_builder/manifests/fbthrift

@@ -23,7 +23,6 @@ fmt
 folly
 googletest
 libsodium
-python-six
 wangle
 zstd
 mvfst