update: change Metadata from type to interface (#8238)

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## Purpose
_Describe the problem you want to address or the feature you want to
implement._

## Approach
_Describe how your changes address the issue or implement the desired
functionality in as much detail as possible._

## References
closes #8231

## Pre-Merge TODO
- [ ] Write tests for your proposed changes
- [ ] Make sure that existing tests do not fail

Co-authored-by: Bayheck <[email protected]>

ts-defs-src/test-api/test-info.d.ts

@@ -1,7 +1,9 @@
 // Test Info
 //----------------------------------------------------------------------------------------------------------------------
 
-type Metadata = Record<string, unknown>;
+interface Metadata {
+    [key: string]: unknown;
+}
 
 interface TestInfo {
     name: string;