Resolution for snapshot artifacts is broken when defining multiple repositories with the same hostname

[denisrosca]

Snapshot dependency resolution is broken if multiple repositories with the same hostname are defined in smithy-build.json.

The underlying aether resolution relies on the repository definition to have a discriminator id for de-duplicating repositories.
The current smithy build definition doesn't have that, thus resolution fails.

Steps to reproduce

Consider the following smithy definition:

{
    "version": "1.0",
    "maven": {
        "repositories": [
            {
                "url": "http://localhost:1234/artifactory-1"
            },
            {
                "url": "http://localhost:1234/artifactory-2"
            }
        ],
        "dependencies": [
            // Normally, this could refer to SMITHY_VERSION, but that doesn't work for pre-release builds.
            "com.example:artifact:1.0.0-SNAPSHOT"
        ]
    }
}

and the following pom file definition for com.example:artifact:1.0.0-SNAPSHOT:

<?xml version='1.0' encoding='UTF-8'?>
<project xsi:schemaLocation=\"http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd\" xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\" xmlns=\"http://maven.apache.org/POM/4.0.0\">
    <modelVersion>4.0.0</modelVersion>
    <groupId>com.example</groupId>
    <artifactId>artifact</artifactId>
    <packaging>jar</packaging>
    <description>artifact</description>
    <version>1.0.0-SNAPSHOT</version>
    <name>artifact</name>
    <organization>
        <name>com.example</name>
    </organization>
    <properties>
        <info.versionScheme>early-semver</info.versionScheme>
    </properties>
    <dependencies>
        <dependency>
            <groupId>com.example</groupId>
            <artifactId>dependency</artifactId>
            <version>1.0.0</version>
        </dependency>
    </dependencies>
</project>

After configuring

• http://localhost:1234/artifactory-1 to host the release version of com.example:dependency:1.0.0
• http://localhost:1234/artifactory-2 to host the snapshot version of com.example:artifact:1.0.0-SNAPSHOT

We would expect the dependency resolution to succeed, but instead it fails.

Fixed by #1884 and 6e68005 adds a test to exemplify the behavior.