Merge bitcoindevkit/bdk#1620: feat(bdk_electrum): add `use-openssl` as a feature

f602d1bfe24783449a88d5e82ab29f305cd2a02c feat(bdk_electrum): add `use-openssl` as a feature (Leonardo Lima)

Pull request description:

  partially addresses #1598

  <!-- You can erase any parts of this template not applicable to your Pull Request. -->

  ### Description

  It's a simple PR to expose the `use-openssl` from `electrum-client` to `bdk_electrum`. It partially addresses #1598, allowing the user to use `openssl` as an alternative to `rustls`, as there are some problems with it when handling some types of TLS certificates.

  Do we need to add some sort of `bdk_electrum` tests using the new exposed `use-openssl` feature ?

  <!-- Describe the purpose of this PR, what's being adding and/or fixed -->

  ### Notes to the reviewers

  <!-- In this section you can include notes directed to the reviewers, like explaining why some parts
  of the PR were done in a specific way -->

  ### Changelog notice

  - Adds `use-openssl` as feature to `bdk_electrum`, exposing `electrum-client` `use-openssl` feature.

  <!-- Notice the release manager should include in the release tag message changelog -->
  <!-- See https://keepachangelog.com/en/1.0.0/ for examples -->

  ### Checklists

  #### All Submissions:

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

  #### New Features:

  * [ ] I've added tests for the new feature
  * [ ] I've added docs for the new feature

  #### Bugfixes:

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

Top commit has no ACKs.

Tree-SHA512: 86e0fdeaa0b6a48e0c7ddde6e3890ce86510b86ad727adf05cde5e8c311a8c6b7614ae57bae0cff9e7b8443478a324e5ce9e5180023d501453a5c1e9e45920e1