Kaustav/update requirements before prepare

Description

This MR fixes two issues :

1. Currently, while creating or updating instances, the instance is prepared before the requirements.txt file is updated. This is fixed.
2. The Grove CLI job was failing due to missing virtual environment. This MR add a virtual environment.

Supporting information

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Testing instructions

Steps to test the changes:

1. TBD

Dependencies

List the dependencies required for this change, if any. Do not forget to link grove-template merge request here if that's affected by this change.

Screenshots

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Checklist

If any of the items below is not applicable, do not remove them, but put a check in it.

• All providers include the new feature/change
• All affected providers can provision new clusters
• Unit tests are added/updated
• Documentation is added/updated
• The TOOLS_CONTAINER_IMAGE_VERSION in ci_vars.yml is updated
• The grove-template repository is updated

Additional context

BB-8616