Conditional resource creation PoC

[ytsarev]

Description of your changes

Conditional resource creation PoC. Use at your own risk :D

A PoC that uses special condition utilizing the provider-terraform Workspace and proceeds with the execution only when VPC with a special name does not exist in the infrastructure. If it does, it breaks the execution with invalid metadata.name intentionally violating RFC1123.

I have:

• Run make reviewable to ensure this PR is ready for review.

How has this code been tested

k apply -f xsubnetblocking.yaml
k apply -f xsubnetnotblocking.yaml

 k get managed
NAME                                                           READY   SYNCED   EXTERNAL-NAME              AGE
subnet.ec2.aws.upbound.io/subnet-with-non-blocking-vpc-9z8z7   True    True     subnet-04455565ce8411aca   41m
subnet.ec2.aws.upbound.io/subnet-with-blocking-vpc-2m87z               False                               4m17s

NAME                                              READY   SYNCED   EXTERNAL-NAME           AGE
vpc.ec2.aws.upbound.io/blockmenotnonblockingvpc   True    True     vpc-0778542c8e5d3324b   41m

NAME                                                         READY   SYNCED   AGE
workspace.tf.upbound.io/subnet-with-non-blocking-vpc-rcprv   True    True     41m
workspace.tf.upbound.io/subnet-with-blocking-vpc-xvm8j       True    True     4m17s

 k get xsubnet
NAME                           SYNCED   READY   COMPOSITION                           AGE
subnet-with-non-blocking-vpc   True     True    xsubnets.aws.platformref.upbound.io   42m
subnet-with-blocking-vpc       False    False   xsubnets.aws.platformref.upbound.io   4m51s

k describe xsubnet subnet-with-blocking-vpc

<omitted for brevity>
Status:
  Block:  -block.me
  Conditions:
    Last Transition Time:  2023-09-13T12:12:59Z
    Message:               cannot compose resources: cannot apply composed resource: cannot create object: VPC.ec2.aws.upbound.io "-block.meblockingvpc" is invalid: metadata.name: Invalid value: "-block.meblockingvpc": a lowercase RFC 1123 subdomain must consist of lower case alphanumeric characters, '-' or '.', and must start and end with an alphanumeric character (e.g. 'example.com', regex used for validation is '[a-z0-9]([-a-z0-9]*[a-z0-9])?(\.[a-z0-9]([-a-z0-9]*[a-z0-9])?)*')
    Reason:                ReconcileError

[bobh66]

Definitely an interesting scenario. It would be nice if AWS would make Name unique and block duplicates at the MR level so this wouldn't be needed. LGTM