[quality][json] Check why we depend on @theia/json in the TS tests

[kittaakos]

Bug Description:

Follow-up of: #8181

Let's check why we have this in the code and how does the test pass?

theia/examples/api-tests/src/typescript.spec.js

Line 115 in 9afc819

.then(function () { return Promise.resolve(require('@theia/json/lib/node/json-backend-module')).then(load) })

Steps to Reproduce:

Additional Information

• Operating System:
• Theia Version:

[tsmaeder]

@kittaakos you openend a PR that removes that dependency, but then close it. Can you comment why?

[vince-fugnitto]

We no longer make use of @theia/json in https://github.com/eclipse-theia/theia/blob/master/examples/api-tests/src/typescript.spec.js.