Fix assetattachments tests

[eccles]

Tests results:

 UNITTEST=testpublicassetattachments.TestPublicAssetAttachmentsInfo task unittests
 task: [about] ./scripts/builder.sh ./scripts/version.sh
 task: [unittests] ./scripts/builder.sh ./scripts/unittests.sh
 Python 3.8.19
  test_assetattachments_info      (unittests.testpublicassetattachments.TestPublicAssetAttachmentsInfo) ... ok
 test_assetattachments_str (unittests.testpublicassetattachments.TestPublicAssetAttachmentsInfo) ... ok

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 Ran 2 tests in 0.001s
 OK

 FUNCTEST=execpublicassets.TestPublicAssetCreate.
 test_asset_create_if_not_exists_with_bad_attachment_assetattachment task functests
 task: [about] ./scripts/builder.sh ./scripts/version.sh
 task: [functests] ./scripts/builder.sh ./scripts/functests.sh
 Python 3.8.19
 test_asset_create_if_not_exists_with_bad_attachment_assetattachment    (functests.execpublicassets.TestPublicAssetCreate) ... ok

 ----------------------------------------------------------------------
 Ran 1 test in 34.616s
 OK

AB#9685