Update scalafmt to 1.5.1 (#6403)
Update scalafmt to 1.5.1 (#6403)

### Problem

The scalafmt plugin is out of date and no longer matches the latest plugins for IntelliJ

### Solution

Update the version to 1.5.1

jsirois/pants,wisechengyi/pants,twitter/pants,wisechengyi/pants,twitter/pants,wisechengyi/pants,benjyw/pants,wisechengyi/pants,tdyas/pants,tdyas/pants,tdyas/pants,twitter/pants,wisechengyi/pants,jsirois/pants,pantsbuild/pants,pantsbuild/pants,tdyas/pants,benjyw/pants,tdyas/pants,pantsbuild/pants,wisechengyi/pants,twitter/pants,benjyw/pants,benjyw/pants,wisechengyi/pants,pantsbuild/pants,benjyw/pants,tdyas/pants,pantsbuild/pants,twitter/pants,tdyas/pants,jsirois/pants,twitter/pants,twitter/pants,tdyas/pants,pantsbuild/pants,wisechengyi/pants,benjyw/pants,wisechengyi/pants,twitter/pants,pantsbuild/pants,benjyw/pants,tdyas/pants,twitter/pants