Run BDK tests with github linux-arm runner

[notmandatory]

Describe the enhancement

Currently BDK CI build-test job tests against the ubuntu-latest image. Github now offers a ubuntu-24.04-arm runner that we should also run the tests with.

https://docs.github.com/en/actions/using-github-hosted-runners/using-github-hosted-runners/about-github-hosted-runners#standard-github-hosted-runners-for-public-repositories

Use case

BDK apps that are hosted in AWS might use their new Graviton servers that are based on ARM and should be tested with the ubuntu-24.04-arm Github runners.

Additional context

https://github.com/actions/partner-runner-images/blob/main/images/arm-ubuntu-24-image.md

[ItshMoh]

Hey @notmandatory On looking the .github/workflows. I found that in this workflow https://github.com/bitcoindevkit/bdk/blob/master/.github/workflows/cont_integration.yml build-test is being done. Now for adding the
ubuntu-24.04-arm as a os. I have done something like this.

build-test:
    needs: prepare
    name: Build & Test
    runs-on: ${{ matrix.os }}
    strategy:
      matrix:
        os:
          - ubuntu-latest
          - ubuntu-24.04-arm64

I have also raised a PR(bitcoindevkit/bdk#1905) for this issue. You can review it.