Change metadata.name in catalog-info.yaml to match accelerator name

[trisberg]

The name in the catalog-info.yaml file should match the accelerator name so someone using the defaults to generate a project could use this file to register the component with the Backstage catalog.

metadata:
  name: sample-app

This applies to weatherforecast-csharp and weatherforecast-steeltoe samples.

[doddatpivotal]

Will also require associated updates to accelerator.yaml

[dmbelyaev]

There is no need to update weatherforecast-csharp and weatherforecast-steeltoe cause this dummy name (sampl-app) will always be replaced during an accelerator execution.

But there are 2 other accelerators where there is no name replacement at all: appsso-starter-java and spring-smtp-gateway. We'll update these 2 in the scope of this task.