Fix: Gradle plugin tests failing with Java 23

[anna-megalou]

Fix Gradle plugin tests failing with Java 23

While building the project, the module openapi-generator-gradle-plugin
failed with 26 test failures when running tests parameterized with
Gradle 8.5.

Error observed:
BUG! exception in phase 'semantic analysis' in source unit 'BuildScript'
Unsupported class file major version 67

Root cause:
The tests were executed on Java 23. Gradle 8.5 does not support
running on Java 23, which causes Groovy compilation failures.
According to the Gradle compatibility matrix, Java 23 support
starts with Gradle 8.10.

Solution:
Update the Gradle version used in the test parameter providers
from 8.5 to 8.10 in the following files:

• GenerateTaskUpToDateTest.kt
• GenerateTaskFromCacheTest.kt
• GenerateTaskConfigurationCacheTest.kt
• ValidateTaskDslTest.kt

After the change all tests pass successfully.

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Summary by cubic

Updated Gradle versions used in openapi-generator-gradle-plugin tests to 8.10 to fix failures on Java 23. Prevents Groovy compile errors seen with Gradle 8.5.

• Bug Fixes
  • Switched test DataProviders from 8.5 to 8.10 in GenerateTaskUpToDateTest.kt, GenerateTaskFromCacheTest.kt, GenerateTaskConfigurationCacheTest.kt, and ValidateTaskDslTest.kt.
  • All tests now pass on Java 23.

^{Written for commit 1d7a995. Summary will update on new commits.}

[cubic-dev-ai]

No issues found across 4 files

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[wing328]

lgtm. thanks for the PR