lib/codeintel: fix newline warning in go1.18

Created by: keegancsmith

go1.18 has new warnings for Println usages which trigger go test to fail:

codeintel/tools/lsif-repl/main.go:63:5: fmt.Println arg list ends with redundant newline
codeintel/tools/lsif-repl/main.go:145:4: fmt.Println arg list ends with redundant newline

I kept the same output, but made the newline explicit to avoid the failure.

Test Plan: go test with go1.18 locally