* Remove an extraneous backslash and reformat the affected command.

Also, in case of a failure the testing is continued for all SIMD
architectures.

* Dev container added to build and debug the project
* Docker image used for CI is updated to can be used as a base for the
  dev container.
* CI script updated minimally to can be run without root privileges.

Co-authored-by: Michael Platings <michael.platings@arm.com>