fix: Graceful error handling for port already in use

[hnnasit]

Which issue(s) does this change fix?

#5346

Why is this change necessary?

When debugging port is provided as -d option and the port is already in use, sam cli throws a trace error.

How does it address the issue?

This PR handles the above exception gracefully with the following message Ports are not available: exposing port TCP 127.0.0.1:<port_num> -> 0.0.0.0:0: listen tcp 127.0.0.1:<port_num>: bind: address already in use.

What side effects does this change have?

N/A

Mandatory Checklist

PRs will only be reviewed after checklist is complete

• Add input/output type hints to new functions/methods
• Write design document if needed (Do I need to write a design document?)
• Write/update unit tests
• Write/update integration tests
• Write/update functional tests if needed
• make pr passes
• make update-reproducible-reqs if dependencies were changed
• Write documentation

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

[mildaniel]

Thanks for this!