v0.0-427-g3c535e1: Fix alignment when first column (direction) is missing.

Test case now produces:
  module somefunction (
      input logic clk,
      input int   a,
            int   b
  );
  endmodule

Even if this code is not style-compliant, the alignment helps visualize the
empty cells, and can alert a user to what's missing.

issues #28

PiperOrigin-RevId: 314631482