build: reduce download junk in log files (#553)

This PR was generated using Autosynth. 🌈 Synth log will be available here: https://source.cloud.google.com/results/invocations/3fc7c8a6-fbba-4d19-9ef9-7d740e5ce776/targets - [ ] To automatically regenerate this PR, check this box. Source-Link: googleapis/synthtool@6946fd7

Author: yoshi-automation

.kokoro/build.sh

@@ -29,7 +29,7 @@ echo ${JOB_TYPE}
 
 # attempt to install 3 times with exponential backoff (starting with 10 seconds)
 retry_with_backoff 3 10 \
- mvn install -B -V \
+ mvn install -B -V -ntp \
  -DskipTests=true \
  -Dclirr.skip=true \
  -Denforcer.skip=true \

.kokoro/dependencies.sh

@@ -31,7 +31,7 @@ export MAVEN_OPTS="-Xmx1024m -XX:MaxPermSize=128m"
 
 # this should run maven enforcer
 retry_with_backoff 3 10 \
- mvn install -B -V \
+ mvn install -B -V -ntp \
  -DskipTests=true \
  -Dclirr.skip=true
 
@@ -86,4 +86,4 @@ then
 else
  msg "Errors found. See log statements above."
  exit 1
-fi
+fi

synth.metadata

@@ -4,7 +4,7 @@
  "git": {
  "name": ".",
  "remote": "https://github.com/googleapis/java-asset.git",
- "sha": "911e403a2d149f24a40bc7c99021777542ab6a8a"
+ "sha": "f71ffb8297d0049ad7bbb67fb4f69b7001d38008"
  }
  },
  {
@@ -51,7 +51,7 @@
  "git": {
  "name": "synthtool",
  "remote": "https://github.com/googleapis/synthtool.git",
- "sha": "1aeca92e4a38f47134cb955f52ea76f84f09ff88"
+ "sha": "6946fd71ae9215b0e7ae188f5057df765ee6d7d2"
  }
  }
  ],