chore: minimize noise from build scripts (#521)

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Source-Link: googleapis/synthtool@1c0c698

.kokoro/coerce_logs.sh

@@ -28,7 +28,6 @@ job=$(basename ${KOKORO_JOB_NAME})
 echo "coercing sponge logs..."
 for xml in `find . -name *-sponge_log.xml`
 do
-  echo "processing ${xml}"
   class=$(basename ${xml} | cut -d- -f2)
   dir=$(dirname ${xml})/${job}/${class}
   text=$(dirname ${xml})/${class}-sponge_log.txt

synth.metadata

@@ -19,7 +19,7 @@
       "git": {
         "name": "synthtool",
         "remote": "https://github.com/googleapis/synthtool.git",
-        "sha": "8f76a885deaaf2fe234daeba4a8cc4d1b3de8086"
+        "sha": "1c0c698705e668ccb3d68556ae7260f16ce63a6e"
       }
     }
   ],