Do not pretend to cache rust build artifacts, speed up CI by ~20%

[alamb]

Which issue does this PR close?

re #2149

Rationale for this change

Caching rust build artifacts (aka the contents of target) is notoriously difficult (as the slightest change in various environments or dependencies often causes a significant recompile).

However, the CI jobs spent a non trivial amount of time attempting to cache the artifacts unsuccessfully (as my measurements below will show). Until someone has some time to get the caching working properly, I propose we simply stop trying and save ourselves some time (and github worker rate-limit credits)

What changes are included in this PR?

Remove the linux-build-lib job as it gates other jobs from starting but does not save any time

Are there any user-facing changes?

Hopefully faster CI

Master PR before this change: https://github.com/apache/arrow-rs/pull/2144/checks
Rust run took: 38m 44s: https://github.com/apache/arrow-rs/actions/runs/2724270288/usage

This PR: https://github.com/apache/arrow-rs/pull/2150/checks
Rust run took: 30 m39s: https://github.com/apache/arrow-rs/actions/runs/2724923930/usage

[codecov-commenter]

Codecov Report

Merging #2150 (b327e4e) into master (19a7189) will increase coverage by 0.00%.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master    #2150   +/-   ##
=======================================
  Coverage   82.86%   82.86%           
=======================================
  Files         237      237           
  Lines       61296    61296           
=======================================
+ Hits        50792    50793    +1     
+ Misses      10504    10503    -1     

Impacted Files	Coverage Δ
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%)	⬆️

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[alamb]

cc @tustvold

[ursabot]

Benchmark runs are scheduled for baseline = 19a7189 and contender = 7560fbd. 7560fbd 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