Adding schematic diagram to walkercreek

[tives82]

I've created a schematic diagram for the walkercreek pipeline. This PR is only to add this diagram.

• added walkercreek.schematic.dark.png and walkercreek.schematic.light.png to docs/images
• updated README.md to reflect diagram

[github-actions]

nf-core lint overall result: Passed ✅ ⚠️

Posted for pipeline commit 5a9bda8

+| ✅  16 tests passed       |+
#| ❔   6 tests were ignored |#
!| ❗   2 tests had warnings |!

❗ Test warnings:

• pipeline_todos - TODO string in WorkflowMain.groovy: Add Zenodo DOI for pipeline after first release
• pipeline_todos - TODO string in meta.yml: #Add a description of all of the variables used as input

❔ Tests ignored:

• files_exist - files_exist
• nextflow_config - nextflow_config
• files_unchanged - files_unchanged
• actions_awstest - actions_awstest
• multiqc_config - multiqc_config
• modules_structure - modules_structure

✅ Tests passed:

• actions_ci - '.github/workflows/ci.yml' is triggered on expected events
• actions_ci - '.github/workflows/ci.yml' checks minimum NF version
• readme - README Nextflow minimum version badge matched config. Badge: 22.10.1, Config: 22.10.1
• readme - README Nextflow minimum version in Quick Start section matched config. README: 22.10.1, Config: 22.10.1
• pipeline_name_conventions - Name adheres to nf-core convention
• template_strings - Did not find any Jinja template strings (129 files)
• schema_lint - Schema lint passed
• schema_lint - Schema title + description lint passed
• schema_lint - Input mimetype lint passed: 'text/csv'
• schema_params - Schema matched params returned from nextflow config
• actions_schema_validation - Workflow validation passed: ci.yml
• actions_schema_validation - Workflow validation passed: fix-linting.yml
• actions_schema_validation - Workflow validation passed: linting.yml
• actions_schema_validation - Workflow validation passed: linting_comment.yml
• merge_markers - No merge markers found in pipeline files
• modules_json - Only installed modules found in modules.json

Run details

• nf-core/tools version 2.7.2
• Run at 2024-06-07 18:13:50

[erinyoung]

Looks clear to me

[erinyoung]

You might want to delete the nf-core github action tests that you're ignoring.