feat(amp): update promtheusservice rulegroupsnamespace

[r0mdau]

Signed-off-by: Romain Dauby romain.dauby@gmail.com

Description of your changes

Updated prometheusservice/amp RuleGroupsNamespace resource with the custom update feature.

Fixes #1480

I have:

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

How has this code been tested

$ k apply -f examples/prometheusservice/workspace.yaml 
workspace.prometheusservice.aws.crossplane.io/example created

$ k get workspace
NAME      READY   SYNCED   EXTERNAL-NAME
example   True    True     ws-651f2dfc-8750-4115-82d9-8d1d2bfa3b9b

$ k apply -f examples/prometheusservice/rulegroupsnamespace.yaml 
rulegroupsnamespace.prometheusservice.aws.crossplane.io/example-rule created
$ k get rulegroupsnamespace
NAME           READY   SYNCED   EXTERNAL-NAME
example-rule   True    True     arn:aws:aps:us-east-1:015890463774:rulegroupsnamespace/ws-651f2dfc-8750-4115-82d9-8d1d2bfa3b9b/example-rule

$ k apply -f examples/prometheusservice/5m-rulegroupsnamespace.yaml

[r0mdau]

The code generation make generate is replacing manually edited code.

I don't know if we should update the code generator or make exceptions in this project Makefile targets. As mentionned in the CODE_GENERATION.md documentation we can make manual edits for Update actions.

[haarchri]

Thanks for Implementation
LGTM

related discussion:

https://crossplane.slack.com/archives/C01718T2476/p1663613389196129?thread_ts=1663613389.196129&cid=C01718T2476