feat: add grpc-web support #102

[Avarei]

Description of your changes

Implements #102

Adds optional fields GRPCWeb and GRPCWebRootPath to providerconfig and hands them over to the argocd client library.

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

Created a cluster object in an argocd behind a proxy without gRPC support. Created another cluster object in an argocd within the same cluster over a k8s service (grpcWeb set to false).

I was not yet able to test GRPCWebRootPath

[Avarei]

I implemented your feedback and successfully ran make reviewable again. I did not test these changes against an argocd yet. I will do that on monday.

[Avarei]

For me everything is working as expected in my cluster and agains my argocd