🌏 convert cram to gvcf to public app

[dmiller15]

Description

This PR creates a public app for the cram to gvcf workflow. It also updates the readme to include the link to the public app and pulls in the pipeline images directly from github so they populate the public app.

Type of change

• [x] New feature (non-breaking change which adds functionality)

How Has This Been Tested?

Please describe the tests that you ran to verify your changes. Provide instructions so we can reproduce. Please also list any relevant details for your test configuration

• [x] Pushed to apps-publisher and it pulls the files appropriately: https://cavatica.sbgenomics.com/u/cavatica/apps-publisher/apps/#cavatica/apps-publisher/kfdrc-gatk-haplotypecaller-workflow

Test Configuration:

• Environment: Cavatica
• Test files: None

Checklist:

• [x] My code follows the style guidelines of this project
• [x] I have performed a self-review of my own code
• [x] I have commented my code, particularly in hard-to-understand areas
• [x] I have made corresponding changes to the documentation
• [x] My changes generate no new warnings
• [x] I have added tests that prove my fix is effective or that my feature works
• [x] New and existing unit tests pass locally with my changes
• [x] Any dependent changes have been merged and published in downstream modules
• [x] I have checked my code and corrected any misspellings