In addition to Robin's answer, the recommended approach is that each developer creates a branch for each feature that they work on, based on the development branch. Then the pull request that is created represents exactly the changes that represent a particular feature or change.
Once a pull request has been reviewed and merged into the development branch, the process you use for merging into your release branch is simplified and separate from the review process.
Stash's documentation on branching and Atlassian's git tutorials explain these concepts in more detail.