add fastcov module

[fischer-hub]

PR checklist

Add nf-core module for fastcov coverage plotting tool. The module was tested with singularity and docker using the container provided by the tools dev. There is currently no conda version available of this tool. Closes #5154

• [x] This comment contains a description of changes (with reason).
• [x] If you've fixed a bug or added code that should be tested, add tests!
• [x] If you've added a new tool - have you followed the module conventions in the contribution docs
• [x] If necessary, include test data in your PR.
• [x] Remove all TODO statements.
• [x] Emit the versions.yml file.
• [x] Follow the naming conventions.
• [x] Follow the parameters requirements.
• [x] Follow the input/output options guidelines.
• [x] Add a resource label
• [ ] Use BioConda and BioContainers if possible to fulfil software requirements.
• Ensure that the test works with either Docker / Singularity. Conda CI tests can be quite flaky:
  • For modules:
    • [x] nf-core modules test <MODULE> --profile docker
    • [x] nf-core modules test <MODULE> --profile singularity
    • [x] nf-core modules test <MODULE> --profile conda
  • For subworkflows:
    • [ ] nf-core subworkflows test <SUBWORKFLOW> --profile docker
    • [ ] nf-core subworkflows test <SUBWORKFLOW> --profile singularity
    • [ ] nf-core subworkflows test <SUBWORKFLOW> --profile conda