chore: set separate cacheDirectory configuration for download-maven-plugin usages

Author: whowes

java-showcase/gapic-showcase/pom.xml

@@ -68,6 +68,9 @@
                 https://raw.githubusercontent.com/googleapis/gapic-showcase/v${gapic-showcase.version}/server/services/compliance_suite.json
               </url>
               <outputDirectory>src/test/resources</outputDirectory>
+              <cacheDirectory>
+                ${project.build.directory}/download-cache
+              </cacheDirectory>
               <!-- Set this to always download the latest version and overwrite the existing file -->
               <overwrite>true</overwrite>
             </configuration>

sdk-platform-java/gapic-generator-java/pom.xml

@@ -125,6 +125,11 @@
         <groupId>com.googlecode.maven-download-plugin</groupId>
         <artifactId>download-maven-plugin</artifactId>
         <version>1.6.8</version>
+        <configuration>
+          <cacheDirectory>
+            ${project.build.directory}/download-cache
+          </cacheDirectory>
+        </configuration>
         <executions>
           <execution>
             <id>download-metadata-proto</id>

sdk-platform-java/java-showcase-3.21.0/gapic-showcase/pom.xml

@@ -60,6 +60,9 @@
                 https://raw.githubusercontent.com/googleapis/gapic-showcase/v${gapic-showcase.version}/server/services/compliance_suite.json
               </url>
               <outputDirectory>src/test/resources</outputDirectory>
+              <cacheDirectory>
+                ${project.build.directory}/download-cache
+              </cacheDirectory>
               <!-- Set this to always download the latest version and overwrite the existing file -->
               <overwrite>true</overwrite>
             </configuration>

sdk-platform-java/java-showcase-3.25.8/gapic-showcase/pom.xml

@@ -68,6 +68,9 @@
                 https://raw.githubusercontent.com/googleapis/gapic-showcase/v${gapic-showcase.version}/server/services/compliance_suite.json
               </url>
               <outputDirectory>src/test/resources</outputDirectory>
+              <cacheDirectory>
+                ${project.build.directory}/download-cache
+              </cacheDirectory>
               <!-- Set this to always download the latest version and overwrite the existing file -->
               <overwrite>true</overwrite>
             </configuration>