fix(delete): deleted related commit_meta_txns for foreign keyconstraint

[cnlangzi]

Changes

Fixes

• fixed fk_reference_objects_commit_meta_txns issue on file deletion #796: related commit_meta_txns should be deleted if reference_object is deleted from postgres without soft deletion. the bug was introduced by Fix/limit thumbnail size #678

Tests

Tasks to complete before merging PR:

• Ensure system tests are passing. If not Run them manually to check for any regressions 📋
• Do any new system tests need added to test this change? do any existing system tests need updated? If so create a PR at 0chain/system_test
• Merge your system tests PR to master AFTER merging this PR

Associated PRs (Link as appropriate):

• 0chain:
• gosdk:
• system_test:
• zboxcli:
• zwalletcli:
• Other: ...

[service-0chain]

Manual system tests [cancelled] with the following config

config	value
tests skipped	FALSE
system-tests	master
gosdk	NOT OVERRIDDEN
zboxcli	staging
zwalletcli	staging
0chain	staging
blobber	staging
authorizer	staging
0box	staging
0block	staging
0dns	staging
explorer	master
0proxy	staging
0search	staging