feat: allow deployment of custom images

[RobPasMue]

Description

Coming from @ans-spohekar's request - being able to pass in a custom image name/tag to deploy

from ansys.geometry.core import launch_docker_modeler

# Using a custom Docker image
modeler = launch_docker_modeler(
    image="myregistry.com/my-geometry:custom-tag"
)

Make sure to pass the full image name though, not just the tag. Give it a try to this branch locally on your side if possible

[RobPasMue]

Let's not merge this one until it has been validated by @ans-spohekar's side

[codecov]

Codecov Report

❌ Patch coverage is 0% with 11 lines in your changes missing coverage. Please review.
✅ Project coverage is 94.90%. Comparing base (3bdb777) to head (4e40a0c).
⚠️ Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
.../ansys/geometry/core/connection/docker_instance.py	0.00%	11 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2625      +/-   ##
==========================================
- Coverage   94.97%   94.90%   -0.07%     
==========================================
  Files         174      174              
  Lines       14488    14498      +10     
==========================================
  Hits        13760    13760              
- Misses        728      738      +10     

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[RobPasMue]

@jacobrkerstetter - ready for review