Remove redirect notice from redirect target (#2104)

README is copied from https://github.com/ROCm/clr which redirects to target
https://github.com/ROCm/rocm-systems/tree/develop/projects/clr

This is correct for https://github.com/ROCm/clr I think, but unnecessary for https://github.com/ROCm/rocm-systems/edit/develop/projects/clr/README.md which is already the correct redirect target.

projects/clr/README.md

@@ -1,6 +1,3 @@
 # AMD CLR - Compute Language Runtimes
 
-> [!CAUTION]
-> The clr repository is retired, please use the [ROCm/rocm-systems](https://github.com/ROCm/rocm-systems/tree/develop/projects/clr) repository for development. This `develop` branch will only accept patch updates from a bot that mirrors clr-specific updates from `rocm-systems` into here.
-
 AMD CLR (Compute Language Runtime) contains source codes for AMD's compute languages runtimes: `HIP` and `OpenCL™`.