Diff of `MainActivity.kt` is wrongly displayed (3x concatenated)

[cortinico]

Bug

The diff of MainActivity.kt is wrong for 0.74:
https://react-native-community.github.io/upgrade-helper/?from=0.73.4&to=0.74.0-rc.0

It seems like if the diff is calling cat on the file 3 times? Not sure what's going on:

React Native versions

0.73.4 to 0.74.0-rc.0

Steps to reproduce

Just go to https://react-native-community.github.io/upgrade-helper/?from=0.73.4&to=0.74.0-rc.0

Describe what you expected to happen:

1. Ideally I'd like to see the correct diff for the file.

[blakef]

I think there's some funk going on with the way we're normalising hunks.

[cortinico]

Fixed by #378