Add mise version+sha256 pinning to CI

[zeitlinger]

Summary

• Pin mise version and sha256 in all workflow files for reproducibility and supply-chain security
• Renovate will keep these up to date via the custom manager in grafana/flint#43

Test plan

• CI passes with pinned mise version

[Copilot]

Pull request overview

This PR strengthens CI reproducibility and supply-chain security by pinning the installed mise binary to an explicit version and sha256 in GitHub Actions workflows, aligning with the Renovate custom manager approach referenced in the PR description.

Changes:

• Add with: version and with: sha256 to jdx/mise-action usage in the lint workflow.
• Add with: version and with: sha256 to jdx/mise-action usage in the acceptance tests workflow.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
.github/workflows/lint.yml	Pins mise version and checksum for deterministic lint runs.
.github/workflows/acceptance-tests.yml	Pins mise version and checksum for deterministic acceptance test runs.

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[Copilot]

Pull request overview

Copilot reviewed 4 out of 4 changed files in this pull request and generated 1 comment.

Comments suppressed due to low confidence (2)

.github/renovate-tracked-deps.json:54

• This PR is scoped as mise pinning, but this hunk also adds new Renovate tracking for grafana/otel-lgtm in docker-compose files. Consider calling out these additional tracked-deps changes in the PR description (or splitting) to keep the change intent clear.

  "examples/dotnet/docker-compose.yml": {
    "docker-compose": [
      "grafana/otel-lgtm"
    ]
  },

.github/renovate-tracked-deps.json:251

• This adds Renovate tracking for the python base image in example Dockerfiles, which isn't mentioned in the PR description. Consider documenting this extra scope so it's clear why renovate-tracked-deps.json changed beyond mise pinning.

  "examples/obi/python.Dockerfile": {
    "dockerfile": [
      "python"
    ]
  },
  "examples/python/Dockerfile": {
    "dockerfile": [
      "python"
    ],

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[zeitlinger]

Thanks @Copilot — addressed 1 comment(s). Please have another look!