feat: adding CI for updater tools

[erickzanardo]

Description

While getting up to speed on the updater_tools, I noticed it didn't had a workflow for itself. This PR adds one.

Type of Change

• [x] ✨ New feature (non-breaking change which adds functionality)
• [ ] 🛠️ Bug fix (non-breaking change which fixes an issue)
• [ ] ❌ Breaking change (fix or feature that would cause existing functionality to change)
• [ ] 🧹 Code refactor
• [ ] ✅ Build configuration change
• [ ] 📝 Documentation
• [ ] 🗑️ Chore

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 96.15%. Comparing base (6ab6972) to head (8092940).

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #166 +/- ## ======================================= Coverage 96.15% 96.15% ======================================= Files 28 28 Lines 3091 3091 ======================================= Hits 2972 2972 Misses 119 119 ``` | [Flag](https://app.codecov.io/gh/shorebirdtech/updater/pull/166/flags?src=pr&el=flags&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=shorebirdtech) | Coverage Δ | | |---|---|---| | [updater_tools](https://app.codecov.io/gh/shorebirdtech/updater/pull/166/flags?src=pr&el=flag&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=shorebirdtech) | `100.00% <ø> (ø)` | | Flags with carried forward coverage won't be shown. [Click here](https://docs.codecov.io/docs/carryforward-flags?utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=shorebirdtech#carryforward-flags-in-the-pull-request-comment) to find out more.

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[erickzanardo]

Nvm, I just realized that we have a matrix that runs for all dart packages! TIL

[erickzanardo]

This already exists in main.yaml. See https://github.com/shorebirdtech/updater/blob/main/.github/workflows/main.yaml#L31-L3

Yeah, I realized that when following up the CI execution 😅, my bad