Remove maven kotlin client tests (already tests in CI)

[wing328]

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---

Summary by cubic

Removes the Kotlin client Maven example and its CI step, modernizes the Spring example to Spring Boot 3 with Springdoc, and adds a dedicated JDK 17 workflow for Maven plugin tests.

• Refactors
  • Deleted modules/openapi-generator-maven-plugin/examples/kotlin.xml and its compile step in .github/workflows/maven-plugin-tests.yaml.
  • Added .github/workflows/maven-plugin-tests-jdk17.yaml; moved the Spring example compile there and removed it from the default workflow.
  • Updated modules/openapi-generator-maven-plugin/examples/spring.xml to spring-boot-starter-parent 3.3.13, replaced Springfox with org.springdoc:springdoc-openapi-starter-webmvc-ui, and removed maven-compiler-plugin.

^{Written for commit 2fe34e0. Summary will update on new commits.}

[cubic-dev-ai]

No issues found across 2 files

[cubic-dev-ai]

1 issue found across 2 files (changes from recent commits).

Prompt for AI agents (unresolved issues)

Check if these issues are valid — if so, understand the root cause of each and fix them. If appropriate, use sub-agents to investigate and fix each issue separately.


<file name=".github/workflows/maven-plugin-tests-jdk17.yaml">

<violation number="1" location=".github/workflows/maven-plugin-tests-jdk17.yaml:32">
P2: Cache key prefix does not match restore-keys prefix, so fallback cache restoration won’t work for caches created by this job.</violation>
</file>

_{Reply with feedback, questions, or to request a fix. Tag @cubic-dev-ai to re-run a review.}

[cubic-dev-ai]

P2: Cache key prefix does not match restore-keys prefix, so fallback cache restoration won’t work for caches created by this job.

Prompt for AI agents

Check if this issue is valid — if so, understand the root cause and fix it. At .github/workflows/maven-plugin-tests-jdk17.yaml, line 32:

<comment>Cache key prefix does not match restore-keys prefix, so fallback cache restoration won’t work for caches created by this job.</comment>

<file context>
@@ -0,0 +1,44 @@
+            ~/.gradle
+            !~/.gradle/caches/*/plugin-resolution/
+            !~/.m2/repository/org/openapitools/
+          key: ${{ runner.os }}-build-${{ env.cache-name }}-${{ hashFiles('**/pom.xml') }}
+          restore-keys: |
+            ${{ runner.os }}-test-maven-plugin-${{ env.cache-name }}-
</file context>