fix golangci-lint issue - tour of beam

[derrickaw]

1. Due to update tour of beam workflow go version #39486 changing the go version to 1.26, the golangci-lint version was out of sync and missed that during testing.
2. This PR updates the golangci-lint versions and fixes go file issues found by the newer golint versions.

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[gemini-code-assist]

Caution

The consumer version of Gemini Code Assist on GitHub has been sunset. All code review activity has officially ceased.