Fixes to make "make sdk-test" to run standalone

[koletzilla]

Summary

Those tests are mostly exercises by the ./destination/main_e2e_test.go file, but they fail if the are run straignt with make sdk-test:
Fixes

• default_configuration.txt was being used as an input file and it was failing because of it. Renaming it so it definetively skips it
• table_to_truncate was being used by two different test, failing because the table already existed.

Pending things:

• input_change_pk_and_all_columns.json fails because it tries to drop one column.
• Update to latest sdk-tester, which is 2.26.0127.001 at the time I'm writing this https://console.cloud.google.com/artifacts/docker/build-286712/us/public-docker-us/sdktesters-v2%2Fsdk-tester?invt=Abm4dQ&inv=1
• Apart from this but related: check if it's worth it to add input_truncate_before.json and input_truncate_then_sync.json to main_e2e_test.go as these are not getting exercised from the tests in that file