v0.5.0

Highlights:

• don't submit failed requests to CTA
• sign RPM packages (girlab pipeline)
• use almalinux (gitlab pipeline)

Changelog for v0.4.0..v0.5.0
* [5b00dfd] [maven-release-plugin] prepare for next development iteration
* [2d0bf7c] gitlab-ci: stop using centos8 images
* [cd57e01] gitlab-ci: always build rpm package
* [892c163] add gpg signing
* [07d79c7] sign rpms
* [3e53b1f] gitlab-ci: fix rpm signing
* [3305ff8] gitlab-ci: improve pipeline dependencies
* [650ba1b] gitlab-ci: add rpm signature verification
* [c3ae090] gitlab-ci: fix importing of rpm keys
* [63b2cbf] gitlab-ci: fixed rpmkeys options
* [6e81d71] gitlab-ci: move rpmkeys import after rpm package installation
* [d2b77e7] gitlab-ci: rework pipeline flow
* [d5f209d] driver: don't submit failed requests to CTA
* [1c694f4] gitlab-ci: fix doggy symbol in rpckeys command
* [ea1fef5] [maven-release-plugin] prepare release v0.5.0