Remove dead pkg_resources fallback for entry_points

[junagent]

Summary

Remove unreachable pkg_resources fallback code in packages/vaex-core/vaex/__init__.py - this is a dead code removal PR.

Problem

The code had a 3-level fallback for importing entry_points:

try:
    from sys import version_info
    if version_info[:2] >= (3, 10):
        from importlib.metadata import entry_points
    else:
        from importlib_metadata import entry_points
except ImportError:
    import pkg_resources
    entry_points = pkg_resources.iter_entry_points

The pkg_resources fallback (the except ImportError: block) is dead code:

• Python 3.9+ (vaex minimum per numpy>=1.19.3,<3) always has importlib.metadata
• importlib.metadata has been stdlib since Python 3.8
• The except ImportError block is never reached

Fix

Replace the 9-line fallback block with a single import:

from importlib.metadata import entry_points

Testing

• No functional change (dead code removal)
• Reduces dependency on setuptools/pkg_resources