Resolve "keycloak login is broken"

Closes #717 (closed)

Keycloak login broken after a keycloak server version upgrade.

Update keycloak-js

Updating keycloak-js requires a newer version of babel, which requires updating react-scripts

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updated to the first version of react-scripts that works: version 5 which is the latest version but is from 2 years ago, the project is no longer supported. If we need to update again we're stuck.

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Cannot get the tests to work because of some lodash function breaking everything. Not sure how to fix, needs investigation.

This needs thorough manual testing before deploying to make sure the react-scripts update did not break anything as it handles the whole bundling and compilation pipeline.