docs: Add scripts overview to readme

[martinalbert]

Description

Adds overview of scripts for testing to README.

Motivation and Context

Informations relevant to repository.

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• I have read the CONTRIBUTING document.
• I haven't repeated the code. (DRY)
• I have added tests to cover my changes.
• All new and existing tests passed.

[jnv]

Good start, but it's very detailed, perhaps it would be helpful to document a quick start or a common testing flow, like "record, with_new_traffic, check recordings, update_traffic, commit"

[jnv]

Now in the contributing guide it's 👍 from me, but I think either Ondra or Jakub should have final word in this because they know the context better, so I am removing myself as a reviewer.

[jnv]

Ha, no idea how to remove myself so I will approve to not block the PR.

Anyway, @martinalbert, I'd like one question to be answered regarding the use of globs for files filtering: https://github.com/superfaceai/station/pull/286/files/bcbd5ee81213802be80cca03ecd503ab915269e0#r1013456678

I know that globs can be used and I think it may be worthy of mentioning that, not necessarily in detail, feel free to link to Jest docs for further explanation.

[martinalbert]

@jnv I tried to fix it with different wording because I wasn't able to use globs as an argument (jest only says you can use pattern or file path but does not describe pattern in more detail) Was only able to use globs with testMatch flag.

[martinalbert]

I'm changing the base branch to #263 since this PR contains changes relevant to that PR. This PR will also need to be updated as it contains incorrect information regarding latest major release of testing library (location of recordings, change of recording flow, ... more in its changelog).