Previously, dropping column families was not implemented,
when we eliminated oprules, we replaced the ops with
NotImplementedForDrop, which wasn't sufficient for
dropped columns. The column families are cleaned up
when the column type itself is dropped, so we don't
really need to do much here. To address this, this
patch will add code to only assert that either the
table is being dropped or the column family has been
removed earlier.

Fixes: #99796
Release note: None

…y index

Previously, if a new column family was added during an add
column and an update/insert occurred concurrently, we could
end up writing to this new column family in any primary index.
This was inadequate because if the primary index did not store
the column, then runtime will have trouble reading data from this
table, since after a rollback the added column / column family
will get cleaned up from the table descriptor. To address this,
this patch avoids writing any columns not stored within an index
descriptor.

Fixes: #99950

Release note (bug fix): Concurrent DML while adding
a new column with a new column family can lead to
corruption in the existing primary index. If a rollback
occurs the table may no longer be accessible.

Previously, our DML injection tests only covered happy paths
for schema changes. We recently ran into a bug where the old
primary index was corrupted after DML and left in a bad state
visible only after a rollback. To address this, this patch
adds tests for this specific scenario and adds the ability
to test rollbacks with DML injection.

Epic: none

Release note: None