gofmt: autofix missing newline at EOF

[kseniadumpling]

The issue was with parsing diffpkg.Hunk in parseDiffLines(). The func operated only with lines in hunk.Body. Such body doesn't contain any info about EOF issue, it simply has "-" and "+" with the same content:

INFO [linters_context] DUBUG: printing hunk: &diff.Hunk{OrigStartLine:7, OrigLines:4, OrigNoNewlineAt:30, NewStartLine:7, NewLines:4, Section:"", StartPosition:1, Body:[]uint8{0x20, 0x9, 0x9, 0x72, 0x65, 0x74, 0x75, 0x72, 0x6e, 0x20, 0x31, 0xa, 0x20, 0x9, 0x7d, 0xa, 0x20, 0x9, 0x72, 0x65, 0x74, 0x75, 0x72, 0x6e, 0x20, 0x32, 0xa, 0x2d, 0x7d, 0xa, 0x2b, 0x7d, 0xa}} 
INFO [linters_context] DUBUG: printing h.Body line-by-line 
INFO [linters_context] DUBUG: line 7:           return 1 
INFO [linters_context] DUBUG: line 8:   }         
INFO [linters_context] DUBUG: line 9:   return 2  
INFO [linters_context] DUBUG: line 10: -}         
INFO [linters_context] DUBUG: line 11: +}         
INFO [linters_context] DUBUG: line 11:            

The new code checks OrigNoNewlineAt flag and adds a new line right after the last problematic line (currentOriginalLineNumber + 1)

fixes #3747
fixes #1373

[boring-cyborg]

Hey, thank you for opening your first Pull Request !

[CLAassistant]

All committers have signed the CLA.

[ldez]

Thank you for taking the time to fix this issue.