ARROW-18113: [C++] Add RandomAccessFile::ReadManyAsync

[aucahuasi]

This PR adds the new method RandomAccessFile::ReadManyAsync: to perform asynchronously multiple reads at once.
The idea for this PR is to provide the new method with its default implementation (which is simply iterating over all the ranges).
The next PRs, will provide specific implementations using coalescing (internal::CoalesceReadRanges) for the some io::RandomAccessFile concrete classes (e.g. the cloud ones and perhaps the CUDA buffer reader as well).

Related Jira ticket:
https://issues.apache.org/jira/browse/ARROW-18113

[github-actions]

https://issues.apache.org/jira/browse/ARROW-18113

[github-actions]

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

[ursabot]

Benchmark runs are scheduled for baseline = 4afe710 and contender = 15a3b05. 15a3b05 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
[Failed ⬇️0.17% ⬆️3.09%] test-mac-arm
[Finished ⬇️0.0% ⬆️0.0%] ursa-i9-9960x
[Finished ⬇️1.26% ⬆️0.21%] ursa-thinkcentre-m75q
Buildkite builds:
[Finished] 15a3b054 ec2-t3-xlarge-us-east-2
[Failed] 15a3b054 test-mac-arm
[Finished] 15a3b054 ursa-i9-9960x
[Finished] 15a3b054 ursa-thinkcentre-m75q
[Finished] 4afe7103 ec2-t3-xlarge-us-east-2
[Failed] 4afe7103 test-mac-arm
[Finished] 4afe7103 ursa-i9-9960x
[Finished] 4afe7103 ursa-thinkcentre-m75q
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