[#81] configure unit tests with vitest

[JanJaroszczak]

Implementation of unit tests made with Vitest.
Test were written for utils functions used in the project.

• related issue
• My changes generate no new warnings
• My code follows the style guidelines of this project
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the changelog
• I have added tests that prove my fix is effective or that my feature works

[MSzalowski]

Provide better PR description pls (remove default).

You could also update README informing about tests (technology used & how to run them)

[Ryun1]

In future can we please try and keep the pull requests smaller, as per the agreed Working Conventions, keeping PRs "Well-scoped - we prefer multiple PRs, rather than a big one"

[MSzalowski]

In future can we please try and keep the pull requests smaller, as per the agreed Working Conventions, keeping PRs "Well-scoped - we prefer multiple PRs, rather than a big one"

Good point. For example that pr could be split into:

1. Vitest integration - just config - no other tests included.
2. Utils tests without including changes src/vva-fe/src/utils/getGovActionId.ts and test for that file - as it provides changes to the utility itself, not just tests.
3. src/vva-fe/src/utils/getGovActionId.ts + test for the utility.

I wonder if in such cases where multiple PRs are about the same functionality (based on the above - vitest config brings nothing without tests) - wouldn't it be better, to have one global branch that would have smaller PRs to that branch and when they all are merged that global branch would have pr (big one - but with all the already reviewed and checked changes from smaller PRs) to main - just a typical git flow - would it be acceptable @Ryun1?

[MSzalowski]

LGTM

[MSzalowski]

@JanJaroszczak Can you rebase that branch to develop?

Based on development process instruction.

[MSzalowski]

I changed the base branch to develop on this PR and rebased (and squashed) commits delivered by @JanJaroszczak with 8c09303

Changes are assigned to me on git, but the author is @JanJaroszczak