feat: add open flag to dfx deploy command

[filippofinke]

Description

This pull request adds a new feature to the dfx deploy command where users can specify the --open flag to automatically open the URL of the deployed canisters in the default browser of the machine. This enhancement aims to improve user experience by providing a convenient way to access the deployed canisters immediately after deployment.

How Has This Been Tested?

To test this feature:

• Ensure the dfx command-line tool is installed and configured properly.
• Run the dfx deploy --open command with a project that has deployable canisters.
• Verify that after deployment, the default browser opens with the URL of the deployed canisters.

Checklist:

• [x] The title of this PR complies with Conventional Commits.
• [x] I have edited the CHANGELOG accordingly.
• [x] I have made corresponding changes to the documentation.

[sa-github-api]

Dear @filippofinke,

In order to potentially merge your code in this open-source repository and therefore proceed with your contribution, we need to have your approval on DFINITY's CLA.

If you decide to agree with it, please visit this issue and read the instructions there. Once you have signed it, re-trigger the workflow on this PR to see if your code can be merged.

— The DFINITY Foundation