Add YAML deployment example for Bitbucket Repository block using pull_with_block

[ehab20011]

Overview

This PR adds a missing example to the Bitbucket integration documentation.
The existing page only included Python examples for pulling flow code from a Bitbucket repository.
This update adds a prefect.yaml example showing how to pull code using a Bitbucket Repository block via the pull_with_block deployment step.

This resolves the user confusion described in the linked issue and aligns the Bitbucket integration docs with other Prefect SCM integrations that already provide YAML examples. (Issue this closes #19418)

Checklist

• This pull request references any related issue by including "closes prefect-bitbucket docs need a yaml example #19418"
• This pull request adds new functionality, it includes unit tests that cover the changes
  (N/A — docs-only change)
• If this pull request removes docs files, it includes redirect settings in mint.json.
  (N/A — no files removed)
• If this pull request adds functions or classes, it includes helpful docstrings.
  (N/A — docs-only)

[zzstoatzz]

looks mostly good @ehab20011 - thanks! one comment on the last part

[zzstoatzz]

this is not correct for prefect 3.x, it should be prefect deploy or similar

deployment build CLI is for 2.x, which claude et al still remember

[desertaxle]

The pull_with_block step was added for backwards compatibility and isn't the recommended way to clone from BitBucket. @ehab20011 is there a reason that you would use this pull step over the already documented git_clone pull step?