chore: Bump golangci-lint to v2.11.1

[devin-ai-integration]

Requirements

• I have added test coverage for new or changed functionality
• I have followed the repository's pull request submission guidelines
• I have validated my changes against all supported platform versions

Related issues

Part of a broader effort to bump golangci-lint across LaunchDarkly Go repositories, matching ld-relay#586.

Describe the solution you've provided

Bumps golangci-lint from v2.9.0 to v2.11.1 in the Makefile and removes an unused //nolint:gosec directive in ldhttp/http_transport.go.

The nolint:gosec directive on the tls.Config{RootCAs: ...} line was flagged as unused by nolintlint in v2.11.1 — gosec no longer reports an issue for a tls.Config that only sets RootCAs (Go's default MinVersion is already TLS 1.2+, which is considered secure).

Describe alternatives you've considered

N/A — this is a straightforward tooling version bump.

Additional context

Items for human review

• Verify that removing the //nolint:gosec directive on ldhttp/http_transport.go:193 is safe. The rationale is that gosec no longer flags tls.Config{RootCAs: caCerts} without an explicit MinVersion, since modern Go defaults to TLS 1.2+. If there's a policy reason to keep the directive as documentation, it can be restored.

Link to Devin session: https://app.devin.ai/sessions/45faa2d1c22c41c6beab7ce8e891bc96
Requested by: @keelerm84

---

Note

Low Risk
Tooling-only update plus removal of an unused lint suppression; no runtime behavior changes expected beyond lint results.

Overview
Bumps golangci-lint from v2.9.0 to v2.11.1 via the Makefile linter version pin.

Removes an unused //nolint:gosec comment from ldhttp/http_transport.go where tls.Config{RootCAs: ...} is set, aligning with the newer linter’s checks.

^{Written by Cursor Bugbot for commit 775517a. This will update automatically on new commits. Configure here.}

[devin-ai-integration]

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