docs: update docs.esp-rs.org links to docs.espressif.com

The docs.esp-rs.org domain has expired and now points to unsafe content.

Author: MabezDev

cargo-espflash/README.md

@@ -189,7 +189,7 @@ You can have a local and/or a global configuration file(s):
 
 [`defmt`]: https://defmt.ferrous-systems.com/
 [`defmt` section]: https://github.com/esp-rs/esp-hal/tree/main/esp-println#defmt
-[`defmt` project]: https://docs.esp-rs.org/no_std-training/03_7_defmt.html
+[`defmt` project]: https://docs.espressif.com/projects/rust/no_std-training/03_7_defmt.html
 
 ## Development Kit Support Policy
 

espflash/README.md

@@ -209,7 +209,7 @@ You can have a local and/or a global configuration file(s):
 
 [`defmt`]: https://defmt.ferrous-systems.com/
 [`defmt` section]: https://github.com/esp-rs/esp-hal/tree/main/esp-println#defmt
-[`defmt` project]: https://docs.esp-rs.org/no_std-training/03_7_defmt.html
+[`defmt` project]: https://docs.espressif.com/projects/rust/no_std-training/03_7_defmt.html
 
 ## Development Kit Support Policy