Remove --defmt flag from probe-run

This now gets automatically detected

.cargo/config.toml

@@ -1,6 +1,6 @@
 [target.'cfg(all(target_arch = "arm", target_os = "none"))']
 # TODO(2) replace `$CHIP` with your chip's name (see `probe-run --list-chips` output)
-runner = "probe-run --chip $CHIP --defmt"
+runner = "probe-run --chip $CHIP"
 rustflags = [
   "-C", "linker=flip-link",
   "-C", "link-arg=-Tlink.x",
@@ -21,4 +21,4 @@ target = "thumbv6m-none-eabi"    # Cortex-M0 and Cortex-M0+
 
 [alias]
 rb = "run --bin"
-rrb = "run --release --bin"
+rrb = "run --release --bin"