chore(java): detect sample-secrets in build.sh (#409)

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Source-Link: googleapis/synthtool@bb854b6

.kokoro/build.sh

@@ -79,6 +79,11 @@ samples)
 
     if [[ -f ${SAMPLES_DIR}/pom.xml ]]
     then
+        for FILE in ${KOKORO_GFILE_DIR}/secret_manager/*-samples-secrets; do
+          [[ -f "$FILE" ]] || continue
+          source "$FILE"
+        done
+
         pushd ${SAMPLES_DIR}
         mvn -B \
           -Penable-samples \

synth.metadata

@@ -4,14 +4,14 @@
       "git": {
         "name": ".",
         "remote": "https://github.com/googleapis/java-core.git",
-        "sha": "70f3a5073dc63236f45fd06bd2cc4a044a43c35f"
+        "sha": "a20bce416bfa6556bb7c3518afeca5259fdf23f4"
       }
     },
     {
       "git": {
         "name": "synthtool",
         "remote": "https://github.com/googleapis/synthtool.git",
-        "sha": "0b064d767537e0675fc053e53fca473c5c701fb8"
+        "sha": "bb854b6c048619e3be4e8b8ce8ed10aa74ea78ef"
       }
     }
   ],