Fix target label check in the cargo project generation

[dmikhalin]

What is the goal of this PR?

In Bazel 6.2.0 targets can start with "@//". In project_aspect.bzl we have a target name check that is now updated according to this change in bazel.

[typedb-bot]

PR Review Checklist

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Trivial Change

• [x] 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.
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• [ ] The architecture intuitively reflects the application domain, and is easy to understand.
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• [ ] The architecture is extensible and scalable.