Allow TSInterfaceDeclaration to be default export (#8408)

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| Q                        | A <!--(Can use an emoji 👍) -->
| ------------------------ | ---
| Fixed Issues?            | Fixes #7118
| Patch: Bug Fix?          | Y
| Major: Breaking Change?  | N
| Minor: New Feature?      | N
| Tests Added + Pass?      | Yes
| Documentation PR Link    | 
| Any Dependency Changes?  |
| License                  | MIT

packages/babel-parser/src/plugins/typescript.js

@@ -1535,6 +1535,17 @@ export default (superClass: Class<Parser>): Class<Parser> =>
         cls.abstract = true;
         return cls;
       }
+
+      // export default interface allowed in:
+      // https://github.com/Microsoft/TypeScript/pull/16040
+      if (this.state.value === "interface") {
+        return this.tsParseDeclaration(
+          this.startNode(),
+          this.state.value,
+          true,
+        );
+      }
+
       return super.parseExportDefaultExpression();
     }