Check base url injected into the client via global config object

[CDimonaco]

Description

The base url of the check service, was previously injected into the frontend via an env variable (WANDA_URL), populated at build time.

This behavior leads to a bug where the user cannot add the base url of the check service because that can be only set at assets build time, when we build the image basically. We need to give the user the ability to specify on which path/url is present the check service in their infrastructure. This can be a path "/check_service" or a full url like we can see on the development configuration.

This configuration is then used by axios to compose the base url of the checks frontend library.

This is similar to grafana public url handling.

Jest configuration updated to perform tests with the global config.

The helm chart needs to be updated.

How was this tested?

Automated tests

[arbulu89]

With a superficial review, we would need to update the hack_to_trento guides, as we wouldn't depend anymore on the .env file and this is what the guides describes.
And we could even drop some dotenv dependencies as well

[CDimonaco]

With a superficial review, we would need to update the hack_to_trento guides, as we wouldn't depend anymore on the .env file and this is what the guides describes. And we could even drop some dotenv dependencies as well

you're right, done!