Get rid of yq and jq usage in the che-code entrypoint

[RomanNikitenko]

Depends on:

• Provide env variable with che-code endpoint URL to the tools container #22346

Is your task related to a problem? Please describe

We are going to support running VS Code in the containers that don't include the pre-requisites, see #21778.

At the moment che-code entrypoint depends on the yq and jq tools:

• yq usage
• jq usage

Describe the solution you'd like

The entrypoint should not depend on the yq and jq tools.
Actually yq is used to read /devworkspace-metadata/flattened.devworkspace.yaml file and get CHE_CODE_ENDPOINT.

I think we should have a possibility to get that endpoint as env variable without any complex logic on the entrypoint side.