Fix line spacing

The characters should touch each other horizontally and vertically. That
way, things like half-height block character based QR codes look correct
instead of seeming stretched.

showbits-thermal-printer/src/documents/lib/main.typ

@@ -12,8 +12,8 @@
     fallback: false,
   )
   set par(
-    leading: 8pt, // Between lines
-    spacing: 26pt, // Between paragraphs
+    leading: 6pt, // Between lines
+    spacing: 22pt, // Between paragraphs
   )
   show heading: set text(size: 32pt)
   show heading: set block(above: 8pt, below: 8pt)