Set compatible_with=appengine on GAE targets

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=128475519

java/google/registry/flows/BUILD

@@ -21,6 +21,7 @@ java_library(
         "*.java",
         "**/*.java",
     ]),
+    compatible_with = ["//buildenv/target:appengine"],
     visibility = ["//visibility:public"],
     deps = [
         ":soy_java_wrappers",
@@ -59,5 +60,6 @@ java_library(
 closure_java_template_library(
     name = "soy_java_wrappers",
     srcs = glob(["soy/*.soy"]),
+    compatible_with = ["//buildenv/target:appengine"],
     java_package = "google.registry.flows.soy",
 )