Add object-store labels to PRs

[alamb]

Which issue does this PR close?

re #2030

Rationale for this change

automatically assigning labels to PRs to assists in reviews and categorization

What changes are included in this PR?

automatically add object-store label to PRs

Are there any user-facing changes?

no

[codecov-commenter]

Codecov Report

Merging #2146 (21467ef) into master (19a7189) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master    #2146   +/-   ##
=======================================
  Coverage   82.86%   82.86%           
=======================================
  Files         237      237           
  Lines       61296    61296           
=======================================
  Hits        50792    50792           
  Misses      10504    10504           

Impacted Files	Coverage Δ
...row/src/array/builder/string_dictionary_builder.rs	90.64% <0.00%> (-0.72%)	⬇️
parquet/src/encodings/encoding.rs	93.43% <0.00%> (-0.20%)	⬇️
parquet_derive/src/parquet_field.rs	65.98% <0.00%> (+0.22%)	⬆️
arrow/src/datatypes/datatype.rs	63.00% <0.00%> (+0.31%)	⬆️

Help us with your feedback. Take ten seconds to tell us how you rate us.

[ursabot]

Benchmark runs are scheduled for baseline = 7560fbd and contender = aa5c849. aa5c849 is a master commit associated with this PR. Results will be available as each benchmark for each run completes.
Conbench compare runs links:
[Skipped ⚠️ Benchmarking of arrow-rs-commits is not supported on ec2-t3-xlarge-us-east-2] ec2-t3-xlarge-us-east-2
[Skipped ⚠️ Benchmarking of arrow-rs-commits is not supported on test-mac-arm] test-mac-arm
[Skipped ⚠️ Benchmarking of arrow-rs-commits is not supported on ursa-i9-9960x] ursa-i9-9960x
[Skipped ⚠️ Benchmarking of arrow-rs-commits is not supported on ursa-thinkcentre-m75q] ursa-thinkcentre-m75q
Buildkite builds:
Supported benchmarks:
ec2-t3-xlarge-us-east-2: Supported benchmark langs: Python, R. Runs only benchmarks with cloud = True
test-mac-arm: Supported benchmark langs: C++, Python, R
ursa-i9-9960x: Supported benchmark langs: Python, R, JavaScript
ursa-thinkcentre-m75q: Supported benchmark langs: C++, Java

[alamb]

Some evidence it is working:

🎉