FEAT: Revamp Build Pipeline to include Alpine Builds and Few test corrections (#170)

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[AB#38107](https://sqlclientdrivers.visualstudio.com/c6d89619-62de-46a0-8b46-70b92a84d85e/_workitems/edit/38107)

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### Summary   
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This pull request introduces improvements to platform detection for
Linux builds in `setup.py` and enhances the performance testing of
connection pooling in the test suite. The most significant changes are
grouped below:

**Platform detection improvements (build system):**

* Updated `get_platform_info()` in `setup.py` to distinguish between
musl and glibc-based Linux systems, returning `musllinux` tags for
musl-based systems and `manylinux_2_28` for glibc, improving
compatibility with various Linux distributions.

**Testing enhancements (connection pooling):**

* Refactored the connection pooling speed test in
`tests/test_003_connection.py` to use more iterations, median timing
(for robustness against outliers), and a stricter threshold for
performance improvement, ensuring that pooling provides a measurable
benefit.
* Improved test reliability by adding a warm-up phase to eliminate cold
start effects before timing connection operations.

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Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

Author: bewithgaurav