misspell should ignore go.sum file

[fhs]

misspell complains about spelling in auto-generated file go.sum:

$ mkdir /tmp/foo
$ cd /tmp/foo
$ go mod init example.com/foo
go: creating new go.mod: module example.com/foo
$ go get golang.org/x/sync@37e7f081c4d4
go: finding golang.org/x/sync 37e7f081c4d4
go: finding golang.org 37e7f081c4d4
go: finding golang.org/x 37e7f081c4d4
$ misspell .
go.sum:1:56: "YUO" is a misspelling of "YOU"
$ cat go.sum 
golang.org/x/sync v0.0.0-20181221193216-37e7f081c4d4 h1:YUO/7uOKsKeq9UokNS62b8FYywz3ker1l1vDZRCRefw=
golang.org/x/sync v0.0.0-20181221193216-37e7f081c4d4/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=

[stmcginnis]

I believe this is typically handled by adding go.sum and go.mod to your .misspellignore file.