fix(ruby-client): fix incorrect Date parsing in OneOf

[LuukvH]

Changes Date.parse to Date.iso8601 to fix incorrect type coercion in OneOf contexts. Previously, arbitrary strings matching Date.parse's lenient pattern (e.g., "ABC1") were incorrectly coerced to dates (2025-06-01), when they should have remained as strings.

For example:

• "ABC1" was parsed as Date(2025-06-01) instead of remaining "ABC1"
• This occurred because Date.parse treats the first char as month ('A'=1) and remaining digits as day

The fix ensures only ISO8601 formatted strings (e.g. "2025-06-02") are parsed as dates, improving type safety and preventing unexpected coercion of string values.

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[wing328]

thanks for the pr

please follow step 3 to update the samples when you've time

[LuukvH]

Hi @wing328, I realized I had only partially regenerated the samples earlier — thanks for pointing it out. I've now re-run the full scripts and pushed the updated files. Let me know if anything else is needed!

[wing328]

thanks for the pr

let's give it a try

[wing328]

PR merged

snapshot will be published shortly

please do a test to ensure it's working for your use cases

https://oss.sonatype.org/content/repositories/snapshots/org/openapitools/openapi-generator-cli/7.14.0-SNAPSHOT/

[LuukvH]

@wing328 I’m not seeing a new snapshot yet. I was hoping to test the behavior, but it looks like no new versions have been published. Am I missing something, or could there be an issue with the snapshot generation?