build(java): use ENABLE_FLAKYBOT env variable (#721)

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Source-Link: googleapis/synthtool@ff01716

.kokoro/build.sh

@@ -115,7 +115,7 @@ fi
 # fix output location of logs
 bash .kokoro/coerce_logs.sh
 
-if [[ "${ENABLE_BUILD_COP}" == "true" ]]
+if [[ "${ENABLE_FLAKYBOT}" == "true" ]]
 then
     chmod +x ${KOKORO_GFILE_DIR}/linux_amd64/flakybot
     ${KOKORO_GFILE_DIR}/linux_amd64/flakybot -repo=googleapis/google-oauth-java-client

.kokoro/nightly/integration.cfg

@@ -22,7 +22,7 @@ env_vars: {
 }
 
 env_vars: {
-  key: "ENABLE_BUILD_COP"
+  key: "ENABLE_FLAKYBOT"
   value: "true"
 }
 

.kokoro/nightly/samples.cfg

@@ -33,6 +33,6 @@ env_vars: {
 }
 
 env_vars: {
-  key: "ENABLE_BUILD_COP"
+  key: "ENABLE_FLAKYBOT"
   value: "true"
 }

synth.metadata

@@ -4,14 +4,14 @@
       "git": {
         "name": ".",
         "remote": "https://github.com/googleapis/google-oauth-java-client.git",
-        "sha": "68ae79dfe7f8714db34fe939c1bc32a477a0d73b"
+        "sha": "b9582d89d242008daa05f576cb416f1a00430d78"
       }
     },
     {
       "git": {
         "name": "synthtool",
         "remote": "https://github.com/googleapis/synthtool.git",
-        "sha": "87254ac89a9559864c0a245d6b150406439ce3d8"
+        "sha": "ff01716e16d2c6e87eaf87197b753ac9fcbbed5d"
       }
     }
   ],