Update beam pipeline base Java version to Java 17 (#2328)

.java-version

@@ -0,0 +1 @@
+17

build.gradle

@@ -383,8 +383,9 @@ subprojects {
   apply from: "${rootDir.path}/java_common.gradle"
 
   // When changing Java version here, be sure to update BEAM Java runtime:
-  // in core/build.gradle, search for `flex-template-base-image` and update
-  // the parameter value.
+  // search for `flex-template-base-image` and update the parameter value.
+  // There are at least two instances, one in core/build.gradle, one in
+  // release/stage_beam_pipeline.sh
   sourceCompatibility = JavaVersion.VERSION_17
   targetCompatibility = JavaVersion.VERSION_17
 

release/stage_beam_pipeline.sh

@@ -71,7 +71,7 @@ while (( "$#" > 0 )); do
     "gs://${dev_project}-deploy/${release_tag}/beam/${metadata_basename}" \
     --image-gcr-path "${image_name}:${release_tag}" \
     --sdk-language "JAVA" \
-    --flex-template-base-image JAVA11 \
+    --flex-template-base-image JAVA17 \
     --metadata-file "./core/src/main/resources/${metadata_pathname}" \
     --jar "./core/build/libs/${uberjar_name}.jar" \
     --env FLEX_TEMPLATE_JAVA_MAIN_CLASS="${main_class}" \