build(java): skip javadoc tests during dependencies test (#423)

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Source-Link: googleapis/synthtool@5b0e159

.kokoro/dependencies.sh

@@ -33,6 +33,7 @@ export MAVEN_OPTS="-Xmx1024m -XX:MaxPermSize=128m"
 retry_with_backoff 3 10 \
   mvn install -B -V -ntp \
     -DskipTests=true \
+    -Dmaven.javadoc.skip=true \
     -Dclirr.skip=true
 
 mvn -B dependency:analyze -DfailOnWarning=true

synth.metadata

@@ -4,14 +4,14 @@
       "git": {
         "name": ".",
         "remote": "https://github.com/googleapis/java-core.git",
-        "sha": "e31620a2f7a15853a1acec8c09416953cc4dce09"
+        "sha": "8c0d6fac48f2dd4651dcd4ff7680ee4ad6a35cb1"
       }
     },
     {
       "git": {
         "name": "synthtool",
         "remote": "https://github.com/googleapis/synthtool.git",
-        "sha": "572ef8f70edd9041f5bcfa71511aed6aecfc2098"
+        "sha": "5b0e1592dd7d70b485e157ea4b3eb1704ecbd015"
       }
     }
   ],