GH-34257:[Docs] Update git links/branches from master to main for external projects

[R-JunmingChen]

As shown in #34257, this pull request update the branch in our doc from master to main for the external dependencies who have changed their default branch to main.

What changes are included in this PR?
9 files.
changed link's git repos:
https://github.com/conda-forge/snappy-feedstock
https://github.com/googleapis/google-cloud-cpp
https://github.com/google/highwayhash
https://github.com/dotnet/sourcelink
https://github.com/dotnet/runtime
https://github.com/numpy/numpy
https://github.com/tidyverse/dplyr
https://github.com/apache/orc

Are these changes tested?
no

• Closes: [Docs][Dev] Update git links/branches from master to main for external projects #34257

[github-actions]

• Closes: [Docs][Dev] Update git links/branches from master to main for external projects #34257

[thisisnic]

I've checked all these links and they all are pointing to the right place; thanks for making this update!

[westonpace]

I confirmed that all the new links do exist and seem to be pointing to the correct thing. Thanks!

[westonpace]

Ah, @thisisnic beat me to it 😆 A triple check then!

[ursabot]

Benchmark runs are scheduled for baseline = 29b23cd and contender = 88d39d5. 88d39d5 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 ⬇️0.39% ⬆️0.0%] test-mac-arm
[Finished ⬇️3.83% ⬆️0.0%] ursa-i9-9960x
[Failed ⬇️0.03% ⬆️0.0%] ursa-thinkcentre-m75q
Buildkite builds:
[Finished] 88d39d5d ec2-t3-xlarge-us-east-2
[Failed] 88d39d5d test-mac-arm
[Finished] 88d39d5d ursa-i9-9960x
[Failed] 88d39d5d ursa-thinkcentre-m75q
[Finished] 29b23cde ec2-t3-xlarge-us-east-2
[Finished] 29b23cde test-mac-arm
[Finished] 29b23cde ursa-i9-9960x
[Finished] 29b23cde 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

[ursabot]

['Python', 'R'] benchmarks have high level of regressions.
test-mac-arm