fix: add priority field in debian/control (#3865)

Co-authored-by: Lucas Nogueira <lucas@tauri.studio>

Author: volgar1x

.changes/debian-priority.md

@@ -0,0 +1,5 @@
+---
+"tauri-bundler": patch
+---
+
+Set the Debian control file `Priority` field to `optional`.

tooling/bundler/src/bundle/linux/debian.rs

@@ -203,6 +203,7 @@ fn generate_control_file(
       writeln!(file, " {}", line)?;
     }
   }
+  writeln!(file, "Priority: optional")?;
   file.flush()?;
   Ok(())
 }