ARROW-14984: [CI][Debian] rsync is missing

[kou]

A follow-up of #11567.

https://github.com/ursacomputing/crossbow/runs/4415960154?check_suite_focus=true

+ mkdir -p /build/docs/c_glib
+ rsync -a /usr/local/share/gtk-doc/html/ /build/docs/c_glib
/arrow/ci/scripts/c_glib_build.sh: line 52: rsync: command not found
127

[github-actions]

https://issues.apache.org/jira/browse/ARROW-14984

[github-actions]

⚠️ Ticket has not been started in JIRA, please click 'Start Progress'.

[kou]

@github-actions crossbow submit test-debian-c-glib test-debian-ruby

[github-actions]

Revision: 5a77bfd

Submitted crossbow builds: ursacomputing/crossbow @ actions-1243

Task	Status
test-debian-c-glib
test-debian-ruby

[kou]

+1

[ursabot]

Benchmark runs are scheduled for baseline = e734856 and contender = 93210d6. 93210d6 is a master commit associated with this PR. Results will be available as each benchmark for each run completes.
Conbench compare runs links:
[Finished ⬇️0.0% ⬆️0.0%] ec2-t3-xlarge-us-east-2
[Finished ⬇️0.45% ⬆️0.0%] ursa-i9-9960x
[Finished ⬇️0.35% ⬆️0.04%] ursa-thinkcentre-m75q
Supported benchmarks:
ec2-t3-xlarge-us-east-2: Supported benchmark langs: Python. Runs only benchmarks with cloud = True
ursa-i9-9960x: Supported benchmark langs: Python, R, JavaScript
ursa-thinkcentre-m75q: Supported benchmark langs: C++, Java

[kszucs]

Thanks Kou!