Add image registry option

[cedricve]

Description

Pull Request Title: Add image registry option

Description:

This pull request introduces the ability to specify a global image registry for all Docker images used in the Helm charts. The following changes were made:

1. Chart Version Update:

   • Updated the chart version from 0.71.0 to 0.72.0 in charts/hub/Chart.yaml.

2. Global Image Registry Addition:

   • Added a new global value imageRegistry in charts/hub/values.yaml to specify the Docker image registry (default set to "docker.io/").

3. Template Modifications:

   • Updated all image references in various template files (hub-api.yaml, hub-cleanup.yaml, hub-frontend-demo.yaml, hub-frontend.yaml, hub-monitor-device.yaml, hub-reactivate-subscription.yaml, pipe-analysis.yaml, pipe-counting.yaml, pipe-dominantcolor.yaml, pipe-event.yaml, pipe-export.yaml, pipe-monitor.yaml, pipe-notify-test.yaml, pipe-notify.yaml, pipe-sequence.yaml, pipe-sprite.yaml, pipe-throttler.yaml, pipe-thumbnail.yaml, vault-forwarder.yaml, vault-proxy.yaml) to prepend the global image registry value.

Motivation:

The primary motivation behind this change is to enhance the flexibility and configurability of the Helm charts. By allowing a global image registry to be specified, users can easily switch between different Docker registries (e.g., Docker Hub, private registries) without modifying individual image references across multiple template files.

Benefits:

• Centralized Configuration: Simplifies the process of changing the image registry by centralizing the configuration in the values.yaml file.
• Flexibility: Provides the ability to easily switch between different Docker registries, facilitating better integration with various CI/CD pipelines and deployment environments.
• Consistency: Ensures that all Docker image references are consistently prefixed with the specified image registry, reducing the risk of configuration errors.

This enhancement significantly improves the usability and maintainability of the Helm charts, making it easier for users to deploy the application in different environments with minimal configuration changes.