chore: Update to Smithy 1.39.0

[jbelkins]

Issue #

#1037

Description of changes

Updates the project for breaking changes to the endpoints rule engine in Smithy 1.39.0.

• Update the name and/or location of several Smithy classes.
• The Swift SDK codegen phase currently copies partitions.json out of the Smithy project for use when code-generating endpoint resolvers. This is not desirable because the copy in Smithy is infrequently updated. Eventually, partitions.json will be supplied at build time by the SDK release coordination system, but for now, an up-to-date copy is provided in this project, and will be updated when needed.
• partitions.json is no longer rendered into every endpoint resolver since it is the same for every service client. Instead, one common copy is provided in AWSClientRuntime.
• An unused endpoints.json file is deleted.

Protocol tests:

• It was discovered that Smithy protocol tests for RestJSON were being run twice: once with Smithy tests & again with local tests. The second execution is omitted.
• There are two new protocol tests that fail. They are disabled & tracked by separate tickets.

New/existing dependencies impact assessment, if applicable

No new dependencies were added to this change.

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

[sichanyoo]

lgtm

[dayaffe]

Looks good!