Fix catalog conversion issue in new update endpoint

[lmossman]

What

I discovered a bug in the new update endpoint that was causing one of my CDC acceptance tests to fail.

The issue is when the new update endpoint tries to convert the existing ConfiguredAirbyteCatalog that was stored in the db to an api AirbyteCatalog to then compare with the catalog provided in the update input.

This code first converts the configured catalog to a "protocol" AirbyteCatalog, and then converts that to the "api" AirbyteCatalog on the next line.

The problem is that the CatalogHelpers.configuredCatalogToCatalog() method loses the stream configurations in the conversion, as it just grabs the "stream" half of the ConfiguredAirbyteStream object for each stream:

airbyte/airbyte-protocol/protocol-models/src/main/java/io/airbyte/protocol/models/CatalogHelpers.java

Line 82 in 5edf3fe

.map(ConfiguredAirbyteStream::getStream)

Then, the CatalogConverter.toApi() method just fills in a default configuration for each stream, and that is then used in the getConfigurationDiff comparison. This is bad because it is always comparing the update endpoint input configuration with some default configuration of each stream, instead of comparing the actual configuration in the database.

How

This PR fixes the issue by just using the proper toApi() endpoint in the CatalogConverter class to convert the configured catalog directly to an "api" AirbyteCatalog which preserves the stream configurations, just skipping the bad intermediate convert.

I also updated the "no streams to reset" unit test to validate that it is actually calling getConfigurationDiff on the correct catalogs (and I verified that this caused the test to fail before I added my fix).