Update example and workflow to fix some incompatibility issues.

[jthuangarm]

• Fix workflow:
  1. It is case-sensitive for pack names under Linux system. Therefore, the pack version of ethos-u-core-driver has to be updated to the latest version, resulting other changes in the MLEL_kws example. For example, for Arm::ethos-u-core-driver@1.22.8 vs ARM::ethos-u-core-driver@1.25.2, the first one will fail under Linux.
  2. For MLEL_kws and examples, Test and Model projects have to be built at the same time because of the dependency of $lib(ML_Model) insides the ML_Test.cproject.yml files.
  3. Some packs like CMSIS Core don't have to be download separately during workflow.
• Upload missing dbgconfg, sct and base files
• Update README.md

Note:

• Currently, the AC6 version has been fixed to v6.20.0. An error occurred from the older tensorflow packs while compiling with v6.24.0. Already tried updating the tensorflow packs to the latest, but more incompatibility issues showed up.
• The QeexoAutoML example cannot be tested since the pack is missing which has to be generated by Qeexo. And the main problem is Qeexo requires license to use.

[ReinhardKeil]

I believe that this repo needs simplification and separation of the Docker container from the usage of this docker container.