[BUG]Duplicate subscriptions created when publishing to multiple environments

### Release version

v6.0.1.7

### Describe the bug

When using the APIOps publisher to deploy APIs across multiple environments (e.g., Dev → Test → Prod), subscriptions included in the Git repository result in duplicate subscriptions being created in each environment, even if the displayName and scope are the same.

### Expected behavior

Subscriptions with the same displayName and scope should be treated as the same logical entity and not duplicated in other environments.

Alternatively, subscriptions could be considered runtime-only data and excluded entirely by default, unless explicitly managed.

### Actual behavior

Publishing creates duplicate subscriptions with the same display name but separate keys and internal IDs, leading to confusion and clutter across environments.

### Reproduction Steps

1. Extract from Dev APIM instance using the extractor pipeline — this includes subscriptions/ artifacts.
2. Commit the extracted subscriptions into the APIOps Git repo.
3. Run the publisher pipeline against a different environment (e.g., Test).
4. Observe that new subscriptions with identical displayName are created in Test, instead of reusing or matching existing ones.

Beginnen Sie damit, den für subscriptions/artifacts beschriebenen Ablauf der extractor pipeline und der publisher pipeline über Dev und Test hinweg nachzustellen. Vergleichen Sie, wie subscriptions mit demselben displayName und scope in der Zielumgebung behandelt werden. Als abgeschlossen sollte gelten, dass doppelte logische subscriptions verhindert werden oder standardmäßig ausgeschlossen sind, wenn dieses Verhalten gewählt wurde.

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