ARROW-15378: [C++][Release] GTest linking error during windows verification

[kszucs]

Uninstall gtest and gmock from conda to prevent conflicts with the bundled counterpart.

[github-actions]

https://issues.apache.org/jira/browse/ARROW-15378

[kszucs]

Seems like this is the workaround we use for daily testing https://github.com/apache/arrow/blob/master/ci/appveyor-cpp-setup.bat#L85

[kszucs]

Build is passing here #12187 (comment)

[kszucs]

+1

[ursabot]

Benchmark runs are scheduled for baseline = 84f929c and contender = e9f9d40. e9f9d40 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 ⬇️0.0% ⬆️0.0%] ursa-i9-9960x
[Finished ⬇️0.26% ⬆️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