Docs: fix google_apigee_sharedflow resource name in terraform docs

[jjaniec]

Fix resource name google_apigee_shared_flow to: google_apigee_sharedflow in provider documentation to match the actual resource name

> terraform version
Terraform v1.9.8

> terraform providers
├── provider[registry.terraform.io/hashicorp/google] ~> 6.32

> terraform plan
│ Error: Invalid resource type
│ 
│   on _sharedflow.tf line 9, in resource "google_apigee_shared_flow" "sharedflow":
│    9: resource "google_apigee_shared_flow" "sharedflow" {
│ 
│ The provider hashicorp/google does not support resource type "google_apigee_shared_flow". Did you mean
│ "google_apigee_sharedflow"?

[github-actions]

** WARNING **: This repository is generated by https://github.com/GoogleCloudPlatform/magic-modules. Any changes made directly to this repository will likely be overwritten. If you have further questions, please feel free to ping your reviewer or, internal employees, reach out to one of the engineers. Thank you!