ARROW-8362: [Crossbow] Ensure that the locally generated version is used in the docker tasks

[kszucs]

No description provided.

[kszucs]

@github-actions crossbow submit -g test

[github-actions]

https://issues.apache.org/jira/browse/ARROW-8362

[kszucs]

@github-actions crossbow submit -g test

[github-actions]

Revision: 6dd535b

Submitted crossbow builds: ursa-labs/crossbow @ actions-80

Task	Status
test-conda-cpp
test-conda-python-3.6
test-conda-python-3.7
test-conda-python-3.8
test-conda-r-3.6
test-debian-10-cpp
test-debian-10-go-1.12
test-debian-10-python-3
test-debian-c-glib
test-debian-ruby
test-fedora-30-cpp
test-fedora-30-python-3
test-r-linux-as-cran
test-r-rhub-ubuntu-gcc-release
test-r-rocker-r-base-latest
test-r-rstudio-r-base-3.6-bionic
test-r-rstudio-r-base-3.6-centos6
test-r-rstudio-r-base-3.6-opensuse15
test-r-rstudio-r-base-3.6-opensuse42
test-ubuntu-16.04-cpp
test-ubuntu-18.04-cpp
test-ubuntu-18.04-cpp-cmake32
test-ubuntu-18.04-cpp-release
test-ubuntu-18.04-cpp-static
test-ubuntu-18.04-docs
test-ubuntu-18.04-python-3
test-ubuntu-18.04-r-3.6
test-ubuntu-18.04-r-sanitizer
test-ubuntu-c-glib
test-ubuntu-ruby

[kszucs]

According to the build log pyarrow-0.16.1.dev469 version is used which was generated by crossbow.

[kszucs]

+1

[kszucs]

The build failures are unrelated, merging.