Merge bitcoindevkit/bdk-cli#186: ci: fix code coverage workflow

Merge bitcoindevkit/bdk-cli#186: ci: fix code coverage workflow

48fa1f64a94052cc493b49b2ede4604a579dcc50 ci: fix code coverage workflow (Steve Myers)

Pull request description:

  ### Description

  The code coverage workflow broke and this change fixes it.

  ### Notes to the reviewers

  This is copy/pasted from the bdk repo job of the same name.

  ### Checklists

  #### All Submissions:

  * [x] I've signed all my commits
  * [x] I followed the [contribution guidelines](https://github.com/bitcoindevkit/bdk-cli/blob/master/CONTRIBUTING.md)
  * [x] I ran `cargo fmt` and `cargo clippy` before committing

ACKs for top commit:
  notmandatory:
    Self ACK 48fa1f64a94052cc493b49b2ede4604a579dcc50

Tree-SHA512: 0b5e42ad867044d26d3e38ed5c0229ab3228381e0ee9ccb3c2cdcd16908275562bc0ca64dcb37607c94ecbb410d409afb37c1c7296efd99fc39a778029752274