ci: cache SDK generator and Maven dependencies

Author: jaavid

.github/workflows/generated-conformance.yml

@@ -2,33 +2,57 @@ name: Generated SDK Conformance
 
 on:
   pull_request:
+    paths-ignore:
+      - "docs/**"
+      - "**/*.md"
   push:
     branches: [main]
+    paths-ignore:
+      - "docs/**"
+      - "**/*.md"
   workflow_dispatch:
 
 permissions:
   contents: read
 
+concurrency:
+  group: sdk-java-conformance-${{ github.ref }}
+  cancel-in-progress: true
+
 jobs:
   generate-and-build:
     runs-on: blacksmith-2vcpu-ubuntu-2404
     timeout-minutes: 12
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v7
       - uses: actions/setup-java@v5
         with:
           distribution: temurin
           java-version: '17'
+      - name: Restore OpenAPI generator cache
+        uses: actions/cache@v4
+        with:
+          path: /tmp/openapi-generator-cli.jar
+          key: openapi-generator-cli-7.12.0
+      - name: Restore generated SDK Maven cache
+        uses: actions/cache@v4
+        with:
+          path: ~/.m2/repository
+          key: generated-sdk-m2-${{ runner.os }}-7.12.0
+          restore-keys: |
+            generated-sdk-m2-${{ runner.os }}-
       - name: Fetch immutable contract
         run: |
           curl --fail --location \
             https://raw.githubusercontent.com/CoreLinkPlatform/api-contracts/5bdc07b80c8acbd0617b75e2d7ae3edd17f6324b/openapi/corelink-public-v1.yaml \
             --output /tmp/corelink-public-v1.yaml
-      - name: Fetch pinned generator
+      - name: Fetch pinned generator when uncached
         run: |
-          curl --fail --location \
-            https://repo1.maven.org/maven2/org/openapitools/openapi-generator-cli/7.12.0/openapi-generator-cli-7.12.0.jar \
-            --output /tmp/openapi-generator-cli.jar
+          if [ ! -s /tmp/openapi-generator-cli.jar ]; then
+            curl --fail --location \
+              https://repo1.maven.org/maven2/org/openapitools/openapi-generator-cli/7.12.0/openapi-generator-cli-7.12.0.jar \
+              --output /tmp/openapi-generator-cli.jar
+          fi
       - name: Generate Java client
         run: |
           rm -rf /tmp/corelink-java-sdk