scripts: west_commands: runners: Fix printf-string-formatting (UP031)

Replace printf-style string format.

See https://docs.astral.sh/ruff/rules/printf-string-formatting/

Signed-off-by: Pieter De Gendt <pieter.degendt@basalte.be>

scripts/west_commands/runners/bossac.py

@@ -199,7 +199,7 @@ class BossacBinaryRunner(ZephyrBinaryRunner):
             offset = self.get_image_offset(self.supports('--offset'))
 
             if offset is not None and int(str(offset), 16) > 0:
-                cmd_flash += ['-o', '%s' % offset]
+                cmd_flash += ['-o', str(offset)]
 
         elif dt_chosen_code_partition_nd is not None:
             error_msg = 'There is no CONFIG_USE_DT_CODE_PARTITION Kconfig' \