Remove url-connector http lib dependency, require GlueClientBuilder input to AWSSchemaRegistryClient

[dbottini]

Issue: #120 (Primary)

Description:
AWSSchemaRegistryClient in the common module directly imports the UrlConnectionHttpClient, which can cause classpath friction with AWS SDK in other places where ApacheHttpClient is preferred, and the ServiceLoader can't figure out which client to use. An example of this is when using the Kinesis Client Library v2, their addition of this library pollutes the classpath, when it ideally should've waited for a user to deliberately configure in the UrlConnectionHttpClient through a GlueClient. This change prefers rely on the GlueClient defaults, or gives the user full access to the GlueClient builder. It still reserves the right to add some overrides around endpoint, region, etc.

This does break the bespoke integration with the UrlConnection Proxy Url, and now requires manually configuring the Glue Client. This may further impact scenarios where Proxy Url was specified using one of the higher-order libraries around common, where the user expects GlueSchemaRegistryConfiguration to set everything up. Now, to create an object like GlueSchemaRegistrySerializationFacade, the user has to also create SchemaByDefinitionFetcher which then wraps AWSSchemaRegistryClient which then wraps GlueClient which contains a manually configured UrlConnectionHttpClient with a proxy url.

The url-connection http lib was likely unintentionally added in https://github.com/awslabs/aws-glue-schema-registry/pull/49/files#diff-79d226ed87c480fcfac3a55dfae33d93c29b6b43f7eebbb1369a4557581431bd, and the proxy url functionality was cemented on in #246. It's worth noting that the initial issue, #245, was attempting to directly insert a GlueClient, so this is more cohesive with their initial approach.

Related reports of issue:
#127
https://stackoverflow.com/a/75323773

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[dbottini]

It seems there's some old code from my initial attempt before a refactor. I also knocked out one of the constructors - I'll tidy those up.

[dbottini]

retry policy will get automatically filled in by the less-telescoped constructor

[dbottini]

One thing I'm noting here working with this repo is that there's a lot of redundant dependency declarations in the child poms, which leads to errors like leaving lombok as a runtime dependency when it wanted to be provided. I'm not going to boil the ocean in this PR, but did want to clean up lombok at least. I think in the long term, this repo should consider moving the "all children want this dependency" dependencies to a basic <dependency> block rather than <dependencyManagement> to reduce risk of similar errors in the future. Probably every compile-time library, like lombok, should just be globally provided and not included individually.