[#255] Generate sample project as a part of test workflow

[nmint8m]

• Solves Move the "sample project generating" from "after merging new PRs into develop" to "directly refreshing the updates on each PR" #255

What happened 👀

In this PR, I did the following requirements:

• move the current workflow generate_sample.yml to be a new job of test.yml.
• the new generate sample job needs generate_mason_bundle
• remove the old workflow generate_sample.yml.

Insight 📝

In the job generate_sample_project I add jobs.job_id.needs to generate_mason_bundle to identify that the job generate_mason_bundle must complete successfully before this generate_sample_project job will run

  generate_sample_project:
    needs: generate_mason_bundle

Proof Of Work 📹

Without changes

Skip the job generate_sample_project

With changes

It's successfully built: https://github.com/nimblehq/flutter-templates/actions/runs/5724239412/job/15510486424

The job generate_sample_project passed

There are 2 new commits:

[luongvo]

The rest lgtm

[luongvo]

with token is to checkout repo correctly under bot-nimble account to bypass branch protection https://github.com/nimblehq/flutter-templates/pull/211/files#diff-b6be02f3a9d4c7902a0c7ef15e92a821440068867b5fef0a201f8f254f01e94cR16-R17. I don't think we need it for the bot-account to push a commit to a normal PR.

[luongvo]

@nmint8m please rebase to have the correct task id as #255 instead 🙏

[doannimble]

Apart from @luongvo 's comments, the rest lgtm

[luongvo]

@nmint8m Do you have time to resolve reviews on this PR, please? Or I can help you resolve the rest, as this is an important PR for the rest of the contributions 🙏

[luongvo]

@nmint8m The commit still uses ticket id as 225, not 255 🙏