misc: test union with a member that has the same name

[0marperez]

Issue #

smithy-lang/smithy-kotlin#1129

Description of changes

Adds a test trying to reproduce the issue.
This issue is not reproducible anymore. It seems that an update to the Kotlin compiler has gotten rid of a bug causing it.

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

[sonarqubecloud]

Quality Gate passed

Issues
1 New issue
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[github-actions]

A new generated diff is ready to view.

• No codegen difference in the AWS SDK

[github-actions]

Affected Artifacts

Changed in size

Artifact	Pull Request (bytes)	Latest Release (bytes)	Delta (bytes)	Delta (percentage)
acmpca-jvm.jar	1,173,409	1,166,849	6,560	0.56%
polly-jvm.jar	679,969	677,973	1,996	0.29%
acmpca-jvm.jar closure	9,033,472	9,026,910	6,562	0.07%
appsync-jvm.jar	2,683,855	2,682,671	1,184	0.04%
opensearchserverless-jvm.jar	1,395,575	1,395,148	427	0.03%
medialive-jvm.jar	9,031,500	9,029,118	2,382	0.03%
polly-jvm.jar closure	8,540,032	8,538,034	1,998	0.02%
bedrockagentruntime-jvm.jar	2,719,436	2,718,887	549	0.02%
bedrockagent-jvm.jar	4,763,356	4,762,615	741	0.02%
medialive-jvm.jar closure	16,891,563	16,889,179	2,384	0.01%
appsync-jvm.jar closure	10,543,918	10,542,732	1,186	0.01%
fsx-jvm.jar	3,152,081	3,151,763	318	0.01%
bedrockagent-jvm.jar closure	12,623,419	12,622,676	743	0.01%
bedrockagentruntime-jvm.jar closure	10,663,701	10,663,150	551	0.01%
opensearchserverless-jvm.jar closure	9,255,638	9,255,209	429	0.00%
ec2instanceconnect-jvm.jar	211,900	211,891	9	0.00%
ec2-jvm.jar	29,276,524	29,275,553	971	0.00%
fsx-jvm.jar closure	11,012,144	11,011,824	320	0.00%
ec2-jvm.jar closure	37,136,587	37,135,614	973	0.00%
mturk-jvm.jar	1,216,986	1,216,980	6	0.00%
ec2instanceconnect-jvm.jar closure	8,071,963	8,071,952	11	0.00%
mturk-jvm.jar closure	9,077,049	9,077,041	8	0.00%
globalaccelerator-jvm.jar closure	9,817,700	9,817,694	6	0.00%
kinesisanalyticsv2-jvm.jar closure	10,234,716	10,234,710	6	0.00%
workspaces-jvm.jar closure	11,420,756	11,420,750	6	0.00%

[0marperez]

Refactored into:
smithy-lang/smithy-kotlin#1241