Fixes version and README

[vpetersson]

Minor changes to improve version handling

[Copilot]

Pull request overview

This PR improves version handling by introducing an environment variable-based versioning system for Docker releases and updates documentation formatting for better clarity.

Key Changes:

• Adds environment variable-based version detection as the primary method for getting package version
• Updates README table formatting to use clearer footnote symbols
• Configures Docker build to pass version information via build arguments

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 1 comment.

File	Description
sbomify_action/cli/main.py	Adds environment variable check as the primary version detection method with updated priority documentation
README.md	Updates table footnote symbols from asterisks to daggers/double daggers for improved clarity
Dockerfile	Adds environment variables to capture version metadata from build arguments
.github/workflows/sbomify.yaml	Implements version determination logic and passes build arguments to Docker build

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