community/py3-pygit2: update dependencies

six is no longer required; and a new dependency is necessary.
7 jobs for !8718 with py3-pygit2 in 1 minute and 56 seconds (queued for 2 seconds)
detached
Status Job ID Name Coverage
  Lint
passed #132269
docker-alpine x86_64
lint

00:00:19

 
  Build
passed #132274
docker-alpine ci-build aarch64
build-aarch64

00:01:08

passed #132275
docker-alpine ci-build armv7
build-armv7

00:01:13

passed #132273
docker-alpine ci-build ppc64le
build-ppc64le

00:01:34

passed #132272
docker-alpine ci-build s390x
build-s390x

00:00:39

passed #132271
docker-alpine ci-build x86
build-x86

00:01:11

passed #132270
docker-alpine ci-build x86_64
build-x86_64

00:00:46