chore(deps): update dependency go to 1.26

[renovate]

This PR contains the following updates:

Package	Type	Update	Change
go	uses-with	minor	1.25 → 1.26

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Release Notes

actions/go-versions (go)

v1.26.3: 1.26.3

Compare Source

Go 1.26.3

v1.26.2: 1.26.2

Compare Source

Go 1.26.2

v1.26.1: 1.26.1

Compare Source

Go 1.26.1

v1.26.0: 1.26.0

Compare Source

Go 1.26.0

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Configuration

📅 Schedule: (UTC)

• Branch creation
  • Only on Sunday and Saturday (* * * * 0,6)
• Automerge
  • At any time (no schedule defined)

🚦 Automerge: Enabled.

♻ Rebasing: Whenever PR is behind base branch, or you tick the rebase/retry checkbox.

🔕 Ignore: Close this PR and you won't be reminded about this update again.

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• If you want to rebase/retry this PR, check this box

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This PR was generated by Mend Renovate. View the repository job log.

[cbartz]

Automated merge blocked: CI/CD checks are not 100% passing. Manual review required.

• Test Internal Packages: ❌ failure
• Multiple checks skipped: Test Terraform with Juju, charm-tests, charm-integration-tests, smoke tests, etc.

Please investigate the failing Test Internal Packages job before merging.

[cbartz]

CI/CD Blocked — Manual Review Required

Status after retries: Test Internal Packages still failing after 1 rerun (attempt 2 in progress)
Rerun attempts: 1 completed, 1 queued

Failure analysis

• Failed job: Test Internal Packages in internal_tests.yaml
• Error:

  TestUpdateJob/shouldFailWhenPlatformMissing (server_test.go:1579)
  Expected: 301
  Actual:   307
  

• Root cause: Go 1.26 changed the behavior of net/http.ServeMux — when handling a request with a missing path parameter (like PATCH /api/v1/jobs//job-7 with empty platform), the redirect status changed from 301 Moved Permanently to 307 Temporary Redirect. This is a behavioral change in Go 1.26's HTTP routing, not a flake.
• Historical context: This is new and specific to this Go 1.26 bump. The test passes on main (Go 1.25) because Go 1.25 returns 301.

Possible fix

Update the test expectation in internal/planner/server_test.go line 1579 from 301 to 307:

// Before
expected: 301
// After
expected: 307

Action required

@javierdelapuente @weiiwang01 @yanksyoon @yhaliaw @florentianayuwono — this Renovate PR cannot be auto-merged because the Test Internal Packages check fails due to a Go 1.26 HTTP behavior change. The test expectation at internal/planner/server_test.go:1579 needs to be updated from 301 to 307 to match Go 1.26's net/http behavior.