Currently, the tail command calls $this->line($line), which in turn calls $this->getOutput()->writeln($line). Since the log file is being read with fgets(), $line includes the ending newline character. Passing this to writeln() appends another newline character, resulting in an empty/blank line between each output line:

This change simply directly calls $this->getOutput()->write($line) to avoid appending an extra newline character:

This resolves #12