doc(README): fix docker build arguements

Signed-off-by: ksharizard <code@kshdev.slmail.me>

Author: ksharizard

README.md

@@ -64,14 +64,14 @@ caddy-tailscale includes a Dockerfile for building a Caddy image with the plugin
 This can be built manually, or you can use the pre-built image with:
 
 ```sh
-docker run -it -rm ghcr.io/tailscale/caddy-tailscale
+docker run -it --rm ghcr.io/tailscale/caddy-tailscale
 ```
 
 Mount a custom Caddyfile to `/etc/caddy/Caddyfile` and optionally mount a volume
 to `/config` to persist the default Tailscale state directory:
 
 ```sh
-docker run -it -rm \
+docker run -it --rm \
   -e TS_AUTHKEY="tskey-auth-XXX" \
   -v ./custom.caddyfile:/etc/caddy/Caddyfile -v ./config:config \
   ghcr.io/tailscale/caddy-tailscale