Merge bitcoindevkit/bdk-cli#114: Fix compilation error when using memory database

faa461d3fc8d20cc033859555017792017e87461 Fix compilation error when using memory database (Daniela Brozzoni)

Pull request description:

  This commit also adds the testing for memory database and key value
  database in CI

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  ### Description

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  ### Notes to the reviewers

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  ### 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

  #### Bugfixes:

  * [ ] This pull request breaks the existing API
  * [x] I've added tests to reproduce the issue which are now passing
  * [ ] I'm linking the issue being fixed by this PR

ACKs for top commit:
  notmandatory:
    ACK faa461d3fc8d20cc033859555017792017e87461

Tree-SHA512: 6e841b0e7cc73145a27ba18ff5e02d08cf1c716cf4b12c46831642bbc26a4d3a411905e765a16b22137654e3d6451492ecea9a5c76a4a9949e574d60f7971475