fix: Handle duplicate resource exception and update urllib3

fix: Handle duplicate resource exception and update urllib3

1. Fix duplicate resource exception handling across OpenStack modules:
   - OpenStack SDK changed exception message format
   - Old: 'Multiple matches found for...'
   - New: 'More than one {Resource} exists with the name...'
   - Update exception check to handle both message formats
   - Applied to: image.py, server.py, volume.py

2. Fix server.created_at attribute:
   - Use 'created_at' instead of 'created' for Server objects
   - Bug introduced during shade to openstacksdk migration (2023)
   - Applied to: server.py lines 27, 92

3. Update urllib3 requirement:
   - Change from 'urllib3<2.1.0' to 'urllib3>=1.26.15,<3.0.0'
   - Resolves dependency conflict warnings
   - Supports newer urllib3 2.x while maintaining compatibility

Fixes builder-openstack-cron job failures.

Issue: AttributeError: 'Server' object has no attribute 'created'
Issue: More than one Image/Server/Volume exists with the name
Issue: urllib3 version conflict

Change-Id: I4561bd1092c81c31e730fb21a2788966128049c1
Signed-off-by: Anil Belur <abelur@linuxfoundation.org>