Metadata db is not populated after running a pipeline

[AlexandreBrown]

Describe the bug
When using Pipelines integration, if we specify a metadata db name that is different than the Kubeflow default of metadb then the metadata like artifacts types will still be pushed to a db named metadb.

Steps To Reproduce

1. Specify a name different than metadb when setting up the rds db, let's use the db name kubeflow for this example
2. Install Kubeflow (tested using main branch + manifest v1.4.1)
3. Notice how the database kubeflow gets created correctly
   
   
4. Create a pipeline run that pushes some artifacts
   Eg:

@component()
def test_comp(
    value: float,
    model: Output[Model],
    model_metrics: Output[Metrics]
):
    print(f"model_metrics.path {model_metrics.path}")
    print(f"model.path {model.path}")
        
    model_metrics.log_metric("test_loss", value)

    with open(model_metrics.path, 'w') as metrics_file:
        metrics_file.write(str(model_metrics.metadata))
    with open(model.path, 'w') as model_file:
        model_file.write("Some model data")

5. Verify that the artifacts metadata was pushed to kubeflow db

6. Notice how the db kubeflow does not have a new row in Artifacts
   

7. Verify the table Artifacts in metadb database instead
   

8. Notice how the metadata was pushed to the metadb database instead.

Expected behavior
I expected the metadata to be uploaded to the kubeflow db.

Environment

• Kubernetes version 1.21
• Using EKS (yes/no), if so version? yes eks.4
• AWS service targeted (S3, RDS, etc.) RDS

Screenshots

Additional context
I could be wrong but I suspect that some changes are required to allow the renaming of the metadata db name.
If we take a look at upstream/apps/pipeline/upstream/base/metadata/base/metadata-grpc-deployment.yaml we see the following :

env:
- name: DBCONFIG_USER
  valueFrom:
    secretKeyRef:
      name: mysql-secret
      key: username
- name: DBCONFIG_PASSWORD
  valueFrom:
    secretKeyRef:
      name: mysql-secret
      key: password
- name: MYSQL_DATABASE
  valueFrom:
    configMapKeyRef:
      name: pipeline-install-config
      key: mlmdDb
- name: MYSQL_HOST
  valueFrom:
    configMapKeyRef:
      name: pipeline-install-config
      key: dbHost
- name: MYSQL_PORT
  valueFrom:
    configMapKeyRef:
      name: pipeline-install-config
      key: dbPort

So it looks like the MYSQL_DATABASE is retrieved from upstream/apps/pipeline/upstream/base/installs/generic/pipeline-install-config.yaml
From this config map we can see that the value is hard coded

mlmdDb: metadb

Maybe we'd need to add mlmdDb as a param in awsconfigs/apps/pipeline/params.env ?

[AlexandreBrown]

I can confirm that adding the mlmdDb param in the params.env fixes it, will make a PR for this.