Revert "Connect - Relation on FE Importer (#13213)" (#13313)

This reverts commit cc71394863.

Regression introduced in https://github.com/twentyhq/twenty/pull/13213
The import/export use an upsert logic and when it goes through the
"update" path it fails due to the connect not being implemented yet
(should be in https://github.com/twentyhq/core-team-issues/issues/1230)

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Co-authored-by: prastoin <paul@twenty.com>

packages/twenty-shared/src/utils/indexMetadata/index.ts

@@ -1 +0,0 @@
-export * from './getUniqueConstraintsFields';