Rust discovery, config file not working as expected

I am trying to avoid entering the same commands in each GDB sessions. For this, I have followed the instructions in rust discovery book but the program is not working as mentioned in the book when I run the program through cargo run it is giving the following error:

ts/project/discovery/src/06-hello-world$ cargo run
   error: could not load Cargo configuration  

cargo run --target thumbv7em-none-eabihf
    Finished dev [unoptimized + debuginfo] target(s) in 0.04s
     Running `arm-none-eabi-gdb -q -x openocd.gdb /home/jawwad-turabi/Documents/project/discovery/target/thumbv7em-none-eabihf/debug/led-roulette`
error: could not execute process `arm-none-eabi-gdb -q -x openocd.gdb /home/jawwad-turabi/Documents/project/discovery/target/thumbv7em-none-eabihf/debug/led-roulette` (never executed)

Caused by:
  No such file or directory (os error 2)

My openocd.gdb file contains these content:

   target remote: 3333
    load
    break main
    continue

My config file contain these content:

 [target.thumbv7em-none-eabihf]
   runner = "arm-none-eabi-gdb -q -x openocd.gdb"
   rustflags = [
   "-C", "link-arg=-Tlink.x",
   ]
   +[build]
   +target = "thumbv7em-none-eabihf"

Please change runner = "arm-none-eabi-gdb -q -x openocd.gdb" to this runner = "gdb-multiarch -q -x openocd.gdb". Because, if you are using the Ubuntu 18.04 LTS version then this command will be used as the book mention.

Ubuntu 18.04 or newer / Debian stretch or newer

NOTE gdb-multiarch is the GDB command you'll use to debug your ARM Cortex-M programs

Ubuntu 14.04 and 16.04

NOTE arm-none-eabi-gdb is the GDB command you'll use to debug your ARM Cortex-M programs