Implement Deploy keys managed resource

[Stanislav2017]

Signed-off-by: Stanislav2017 [email protected]

Description of your changes

Added DeployKey api, client side and controller side. Added referencers for relation DeployKey with Project without hardcoded IDs

Fixes https://github.com/crossplane-contrib/provider-gitlab/issues/13

I have:

• [x] Read and followed Crossplane's contribution process.
• [x] Run make reviewable test to ensure this PR is ready for review.

How has this code been tested

manually and tests

[Stanislav2017]

Thanks @Stanislav2017! I believe we are missing the part of the key generation

Added a key generator and corrected the tests. When you will be free, please check

[ChrisJBurns]

What is the status with this, we have realised we want to use this on our projects @Stanislav2017 @janwillies

Additionally, is the gitlab_deploy_key_enable something that can be done also? Otherwise the deploy keys will be created, but someone will have to go in and manually enable them.

[MisterMX]

Superseeded by #76