Add missing -lp shortcut for --launch-profile in dotnet run documentation

[abhiramch018]

This PR adds the missing -lp shorthand for the --launch-profile option in the dotnet run CLI reference.

Changes made:

Added -lp alias alongside --launch-profile

Added clarification note and consistent formatting

Why: The previous documentation omitted the -lp shortcut even though it appears in the official CLI help (dotnet run -h).

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Internal previews

📄 File	🔗 Preview link
docs/core/dependency-loading/default-probing.md	Default probing
docs/core/tools/dotnet-run.md	dotnet run command
docs/machine-learning/how-to-guides/install-gpu-model-builder.md	How to install GPU support in Model Builder