Specify python interpreter when installing pip dependencies for CI

[krishnangovindraj]

Usage and product changes

We now specify the python interpreter when installing pip dependencies for CI. This allows us to ensure the dependencies are installed for the specified toolchain.

Implementation

Introduce a python_interpreter_symlink repository which resolves toolchain based on information from repository_context.os. The symlink for the right version can then be passed to pip_parse as the python_interpreter_target argument.

[vaticle-bot]

PR Review Checklist

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Trivial Change

• [ ] This change is trivial and does not require a code or architecture review.

Code

• [ ] Packages, classes, and methods have a single domain of responsibility.
• [ ] Packages, classes, and methods are grouped into cohesive and consistent domain model.
• [ ] The code is canonical and the minimum required to achieve the goal.
• [ ] Modules, libraries, and APIs are easy to use, robust (foolproof and not errorprone), and tested.
• [ ] Logic and naming has clear narrative that communicates the accurate intent and responsibility of each module (e.g. method, class, etc.).
• [ ] The code is algorithmically efficient and scalable for the whole application.

Architecture

• [ ] Any required refactoring is completed, and the architecture does not introduce technical debt incidentally.
• [ ] Any required build and release automations are updated and/or implemented.
• [ ] Any new components follows a consistent style with respect to the pre-existing codebase.
• [ ] The architecture intuitively reflects the application domain, and is easy to understand.
• [ ] The architecture has a well-defined hierarchy of encapsulated components.
• [ ] The architecture is extensible and scalable.