[release-22.0] Upgrade the Golang version to go1.24.6

[vitess-bot]

This Pull Request bumps the Golang version to go1.24.6 and the bootstrap version to 43.3.

Do not trust the bot blindly. A thorough code review must be done to ensure all the files have been correctly modified.

There are a few manual steps remaining:

• Make sure you update the Golang version used in the previous and next release branches for the Upgrade/Downgrade tests.
• Build and Push the bootstrap images to Docker Hub, the bot cannot handle that.

cc @vitessio/release

[vitess-bot]

Review Checklist

Hello reviewers! 👋 Please follow this checklist when reviewing this Pull Request.

General

• Ensure that the Pull Request has a descriptive title.
• Ensure there is a link to an issue (except for internal cleanup and flaky test fixes), new features should have an RFC that documents use cases and test cases.

Tests

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Documentation

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• There should be a comment at the top of each new or modified test to explain what the test does.

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Backward compatibility

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• vtctl command output order should be stable and awk-able.

[vitess-bot]

Hello! 👋

This Pull Request is now handled by arewefastyet. The current HEAD and future commits will be benchmarked.

You can find the performance comparison on the arewefastyet website.

[nickvanw]

Closing this in favor of #18621