ci: Remove Nexus jobs/workflows (#937) #2383

Job	Run time
Run Cargo Deny (bans licenses sources)	27s
Run Cargo Udeps	1m 46s
Run Cargo Deny (advisories)	24s
Run Rustfmt	26s
Run Clippy	33s
Run RustDoc	1m 13s
Decide if Helm charts are pushed to the helm repository based on action trigger	4s
Check if committed README is the one we would render from the available parts	26s
Run Cargo Tests	36s
Check if committed Helm charts are up to date	56s
All tests passed	4s
Package Charts, Build Docker Image and publish them - ubicloud-standard-8-arm	11m 14s
Package Charts, Build Docker Image and publish them - ubuntu-latest	12m 10s
Build and publish manifest list	33s
Run the OpenShift Preflight check on the published images	21s
	31m 13s

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