Modify keyboard shortcuts for long diffs to navigate blocks of changes before changing files
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## Problem to Solve
Currently if you're using a keyboard to navigate diffs in GitLab the `j` and `k` shortcuts only navigate between files. If you have a particularly long file that might have several blocks of changes in it, it can be helpful to navigate through those before navigating to the next file.
## Proposal
We should modify the `j` and `k` shortcuts to jump through the blocks of changes in a file before fully moving on to the next file.
issue