build(node_library): migrate to Trampoline V2 (#329)

Source-Author: Takashi Matsuo <tmatsuo@google.com>
Source-Date: Fri Oct 2 12:13:27 2020 -0700
Source-Repo: googleapis/synthtool
Source-Sha: 0c868d49b8e05bc1f299bc773df9eb4ef9ed96e9
Source-Link: googleapis/synthtool@0c868d4

packages/google-cloud-securitycenter/synth.metadata

@@ -4,7 +4,7 @@
       "git": {
         "name": ".",
         "remote": "https://github.com/googleapis/nodejs-security-center.git",
-        "sha": "e7bda5c2b69f28454405acd3deadd264520c7bbc"
+        "sha": "50e2acd424b319c586011e06b0042d0670826762"
       }
     },
     {
@@ -19,7 +19,7 @@
       "git": {
         "name": "synthtool",
         "remote": "https://github.com/googleapis/synthtool.git",
-        "sha": "079dcce498117f9570cebe6e6cff254b38ba3860"
+        "sha": "0c868d49b8e05bc1f299bc773df9eb4ef9ed96e9"
       }
     }
   ],
@@ -92,10 +92,12 @@
     ".kokoro/test.bat",
     ".kokoro/test.sh",
     ".kokoro/trampoline.sh",
+    ".kokoro/trampoline_v2.sh",
     ".mocharc.js",
     ".nycrc",
     ".prettierignore",
     ".prettierrc.js",
+    ".trampolinerc",
     "CODE_OF_CONDUCT.md",
     "CONTRIBUTING.md",
     "LICENSE",