Add slider_perf_android task to ci.yaml

[TahaTesser]

This adds devicelab task slider_perf_android to .ci.yaml, which was added in #125296

Pre-launch Checklist

• I read the Contributor Guide and followed the process outlined there for submitting PRs.
• I read the Tree Hygiene wiki page, which explains my responsibilities.
• I read and followed the Flutter Style Guide, including Features we expect every widget to implement.
• I signed the CLA.
• I listed at least one issue that this PR fixes in the description above.
• I updated/added relevant documentation (doc comments with ///).
• I added new tests to check the change I am making, or this PR is test-exempt.
• All existing and new tests are passing.

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[Piinks]

LGTM! Thanks for thinking of putting these benchmarks in place before the big refactoring!

[Piinks]

Looks like this needs test owner ship defined in https://github.com/flutter/flutter/blob/master/TESTOWNERS

# Test ownership check failed.
Builders missing owner: [Linux_android slider_perf_android]
Please define ownership in https://github.com/flutter/flutter/blob/master/TESTOWNERS

[TahaTesser]

Looks like this needs test owner ship defined in https://github.com/flutter/flutter/blob/master/TESTOWNERS

# Test ownership check failed.
Builders missing owner: [Linux_android slider_perf_android]
Please define ownership in https://github.com/flutter/flutter/blob/master/TESTOWNERS

Thank you! I'm adding this task for the first time.