Citus upgrade might fail due to fkeys between columnar metadata tables having different names in different pg versions

edited by @onurctirtir: For the workaround, see https://github.com/citusdata/citus/issues/5473#issuecomment-972627162.

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The upgrade path from 10.0.3 to 10.1.2 is broken due to the following error. This happens only in a specific scenario where a PG upgrade is also involved. Following are the sequence of steps:

1. We are at Postgres version 11.4 and Citus version 10.0.3
2. Upgraded Postgres to 13.4
3. Now try upgrading Citus to 10.1.2 ----> This FAILS

Following is the error when running the command `ALTER EXTENSION citus UPDATE`:
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