SNOW-1482571: Add CI pipeline for apps unit testing

[sfc-gh-osalazarlizano]

Run tests for n quantity of sub-repos if there are modified files inside them. E.g.

Given the following repo structure:

/native-apps-examples
   |-mailorder
   |          |-*
   |-data-mapping
   |          |-*
   |-account-privileges
   |          |-*
   |...

From the structure above, if there are changes only in mailorder and account-privileges, just the tests for these sub-repos are going to be executed. data-mapping tests don't need to be execute because there are no changes inside the repo.

[sfc-gh-cgorrie]

It might be enough to enforce that each individual app has its own pytest.ini and we can simply delegate to it. I don't think it's necessary to only run changed files -- unless I'm misreading this. Does this just delegate to individual inis?

[sfc-gh-osalazarlizano]

We are dynamically creating that in the root folder since the pytest command needs it in the folder to be executed. We are running tests from modified sub-repos, and this is why the pytest command is run globally and not in the individual app.

[sfc-gh-cgorrie]

Ah got it. OK, that makes sense to me!