minor: leftover from S98 - delete orphaned attachment_contents (LMS-1936)

...s/generic/server/dataaccess/db/DatabaseVersionHolder.java

openbis/source/sql/generic/065/data-065.sql

openbis/source/sql/generic/065/schema-065.sql

openbis/source/sql/postgresql/065/domains-065.sql

openbis/source/sql/postgresql/065/function-065.sql

openbis/source/sql/postgresql/065/grants-065.sql

...bis/source/sql/postgresql/migration/migration-064-065.sql

openbis/sourceTest/sql/postgresql/065/.DUMP

...sourceTest/sql/postgresql/065/001=attachment_contents.tsv

openbis/sourceTest/sql/postgresql/065/002=attachments.tsv

...ceTest/sql/postgresql/065/005=controlled_vocabularies.tsv

...st/sql/postgresql/065/006=controlled_vocabulary_terms.tsv

openbis/sourceTest/sql/postgresql/065/007=data.tsv

...sourceTest/sql/postgresql/065/008=data_set_properties.tsv

...rceTest/sql/postgresql/065/009=data_set_relationships.tsv

...t/sql/postgresql/065/010=data_set_type_property_types.tsv

openbis/sourceTest/sql/postgresql/065/011=data_set_types.tsv

openbis/sourceTest/sql/postgresql/065/014=data_stores.tsv

openbis/sourceTest/sql/postgresql/065/015=data_types.tsv

.../sourceTest/sql/postgresql/065/016=database_instances.tsv